Alkatronic Quick Guide to fixing the disconnects and reconnects on WIFI
Before iOS13, closing the app is fine. But with iOS13 and above, they implemented an auto reconnection of Bluetooth device if it is dropped suddenly.
When you close the app, iOS will try to help you reconnect, but the app isn't doing this as it is closed already. So, while iOS tries to connect to AT, the AT is not responding and therefore this goes in a forever loop.
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