diff --git a/src/apps.js b/src/apps.js
index b45a54ca1..04e8205b7 100644
--- a/src/apps.js
+++ b/src/apps.js
@@ -171,6 +171,7 @@ const appTaskManager = require('./apptaskmanager.js'),
     logs = require('./logs.js'),
     mail = require('./mail.js'),
     manifestFormat = require('@cloudron/manifest-format'),
+    mysql = require('mysql2'),
     notifications = require('./notifications.js'),
     once = require('./once.js'),
     path = require('node:path'),
@@ -1133,11 +1134,13 @@ async function del(id) {
         { query: 'DELETE FROM appEnvVars WHERE appId = ?', args: [ id ] },
         { query: 'DELETE FROM appPasswords WHERE identifier = ?', args: [ id ] },
         { query: 'DELETE FROM appMounts WHERE appId = ?', args: [ id ] },
+        // this removes double quoted "appId" with optional trailing comma from the JSON
+        { query: `UPDATE backupSites SET contentsJson = REGEXP_REPLACE(contentsJson, ${mysql.escape('"' + id + '"(,)?')}, '') WHERE contentsJson LIKE ${mysql.escape('%"' + id + '"%')}`, args: [] },
         { query: 'DELETE FROM apps WHERE id = ?', args: [ id ] }
     ];
 
     const results = await database.transaction(queries);
-    if (results[5].affectedRows !== 1) throw new BoxError(BoxError.NOT_FOUND, 'App not found');
+    if (results[6].affectedRows !== 1) throw new BoxError(BoxError.NOT_FOUND, 'App not found');
 }
 
 async function clear() {