diff --git a/watchtower-plugin/src/convert.rs b/watchtower-plugin/src/convert.rs
index d49889ca..a2acd576 100644
--- a/watchtower-plugin/src/convert.rs
+++ b/watchtower-plugin/src/convert.rs
@@ -289,44 +289,56 @@ impl TryFrom<serde_json::Value> for GetRegistrationReceiptParams {
         match value {
             serde_json::Value::Array(a) => {
                 let param_count = a.len();
-                if param_count == 2{
-                    Err(GetRegistrationReceiptError::InvalidFormat(("Both ends of boundary (subscription_start and subscription_expiry) are required.").to_string()))
+                if param_count == 2 {
+                    Err(GetRegistrationReceiptError::InvalidFormat((
+                        "Both ends of boundary (subscription_start and subscription_expiry) are required.").to_string()
+                    ))
                 } else if param_count != 1 && param_count != 3 {
                     Err(GetRegistrationReceiptError::InvalidFormat(format!(
                         "Unexpected request format. The request needs 1 or 3 parameter. Received: {param_count}"
                     )))
-                } else{
+                } else {
                     let tower_id = if let Some(s) = a.get(0).unwrap().as_str() {
                         TowerId::from_str(s).map_err(|_| {
-                        GetRegistrationReceiptError::InvalidId("Invalid tower id".to_owned())
+                            GetRegistrationReceiptError::InvalidId("Invalid tower id".to_owned())
                         })
                     } else {
                         Err(GetRegistrationReceiptError::InvalidId(
-                        "tower_id must be a hex encoded string".to_owned(),
+                            "tower_id must be a hex encoded string".to_owned(),
                         ))
                     }?;
 
-                    let (subscription_start, subscription_expiry) = if let (Some(start), Some(expire)) = (a.get(1).and_then(|v| v.as_i64()), a.get(2).and_then(|v| v.as_i64())) {
+                    let (subscription_start, subscription_expiry) = if let (Some(start), Some(expire)) = (a.get(1), a.get(2)){
+                        let start = start.as_i64().ok_or_else(|| {
+                            GetRegistrationReceiptError::InvalidFormat(
+                                "Subscription_start must be a positive integer".to_owned(),
+                            )
+                        })?;
+
+                        let expire = expire.as_i64().ok_or_else(|| {
+                            GetRegistrationReceiptError::InvalidFormat(
+                                "Subscription_expire must be a positive integer".to_owned(),
+                            )
+                        })?;
+
                         if start >= 0 && expire > start {
                             (Some(start as u32), Some(expire as u32))
                         } else {
                             return Err(GetRegistrationReceiptError::InvalidFormat(
-                                    "Subscription_start must be a positive integer and subscription_expire must be a positive integer greater than subscription_start".to_owned(),
-                                    ));
+                                "subscription_start must be a positive integer and subscription_expire must be a positive integer greater than subscription_start".to_owned(),
+                            ));
                         }
-                    } else if a.get(1).is_some() || a.get(2).is_some() {
-                        return Err(GetRegistrationReceiptError::InvalidFormat(
-                                "Subscription_start and subscription_expiry must be provided together as positive integers".to_owned(),
-                                ));
                     } else {
                         (None, None)
                     };
 
-                    Ok(Self {
-                    tower_id,
-                    subscription_start,
-                    subscription_expiry,
-                    })
+                    Ok(
+                        Self {
+                            tower_id,
+                            subscription_start,
+                            subscription_expiry,
+                        }
+                    )
                 }
             },
             serde_json::Value::Object(mut m) => {
diff --git a/watchtower-plugin/src/dbm.rs b/watchtower-plugin/src/dbm.rs
index d7cfcb0e..7ee9f388 100755
--- a/watchtower-plugin/src/dbm.rs
+++ b/watchtower-plugin/src/dbm.rs
@@ -218,7 +218,7 @@ impl DBM {
         user_id: UserId,
         subscription_start: Option<u32>,
         subscription_expiry: Option<u32>,
-    ) -> Vec<RegistrationReceipt> {
+    ) -> Option<Vec<RegistrationReceipt>> {
         let mut query = "SELECT available_slots, subscription_start, subscription_expiry, signature FROM registration_receipts WHERE tower_id = ?1".to_string();
 
         let tower_id_encoded = tower_id.to_vec();
@@ -233,8 +233,8 @@ impl DBM {
         }
         let mut stmt = self.connection.prepare(&query).unwrap();
 
-        let receipts = stmt
-            .query_map(params.as_slice(), |row| {
+        Some(
+            stmt.query_map(params.as_slice(), |row| {
                 let slots: u32 = row.get(0)?;
                 let start: u32 = row.get(1)?;
                 let expiry: u32 = row.get(2)?;
@@ -245,10 +245,9 @@ impl DBM {
                 ))
             })
             .unwrap()
-            .collect::<Result<Vec<_>, _>>()
-            .unwrap_or_default();
-
-        receipts
+            .map(|r| r.unwrap())
+            .collect(),
+        )
     }
 
     /// Removes a tower record from the database.
@@ -747,7 +746,8 @@ mod tests {
                 receipt.user_id(),
                 subscription_start,
                 subscription_expiry
-            )[0],
+            )
+            .unwrap()[0],
             receipt
         );
 
@@ -765,7 +765,8 @@ mod tests {
                 latest_receipt.user_id(),
                 subscription_start,
                 latest_subscription_expiry
-            ),
+            )
+            .unwrap(),
             vec![receipt, latest_receipt.clone()]
         );
 
@@ -774,7 +775,8 @@ mod tests {
         dbm.store_tower_record(tower_id, net_addr, &middle_receipt)
             .unwrap();
         assert_eq!(
-            dbm.load_registration_receipt(tower_id, latest_receipt.user_id(), None, None)[0],
+            dbm.load_registration_receipt(tower_id, latest_receipt.user_id(), None, None)
+                .unwrap()[0],
             latest_receipt
         );
     }
@@ -799,7 +801,8 @@ mod tests {
                 receipt.user_id(),
                 subscription_start,
                 subscription_expiry
-            )[0],
+            )
+            .unwrap()[0],
             receipt
         );
 
diff --git a/watchtower-plugin/src/main.rs b/watchtower-plugin/src/main.rs
index f6f19c1b..d80fbbe4 100755
--- a/watchtower-plugin/src/main.rs
+++ b/watchtower-plugin/src/main.rs
@@ -143,7 +143,7 @@ async fn get_registration_receipt(
 
     let response =
         state.get_registration_receipt(tower_id, subscription_start, subscription_expiry);
-    if response.is_empty() {
+    if response.clone().unwrap().is_empty() {
         if state.towers.contains_key(&tower_id) {
             Err(anyhow!("No registration receipt found for {tower_id}"))
         } else {
diff --git a/watchtower-plugin/src/wt_client.rs b/watchtower-plugin/src/wt_client.rs
index 8287628d..59f6d68d 100644
--- a/watchtower-plugin/src/wt_client.rs
+++ b/watchtower-plugin/src/wt_client.rs
@@ -185,7 +185,7 @@ impl WTClient {
         tower_id: TowerId,
         subscription_start: Option<u32>,
         subscription_expiry: Option<u32>,
-    ) -> Vec<RegistrationReceipt> {
+    ) -> Option<Vec<RegistrationReceipt>> {
         self.dbm.load_registration_receipt(
             tower_id,
             self.user_id,