There could be multiple reasons.
1. App hit to your server is not working. This would be visible in ionic serve
2. Cordova is failing to load. conflicting cordova packages.
Best way to debug it would be to prepare debug version of the app. The connect it with your computer, open chrome and type inspect://devices and then inspect the ionic app. In the networking sub-tab you should see the hits being sent out from the app to your server using the server key.
Check what the server is outputting.
Also, share the device where you’re testing. Did it work on chrome ?
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