I have gone to the MTA Sams customer service in Istanbul turkey. following day, they said there is no problem with the Bluetooth. Then, we have checked a blueBluet device of them and see connection problems. Still they don't want to accept there is a problem. this is shameful for the Samsung.
I have the same issue with A51 I test my headset with multiple devices and it works fine ,but with my A51 its keep disconnecting. I hope it's not hardware related issue .
Contacted Samsung Support and their help desk robots gave me the usual diagnostic steps. Clear the cache, reset network settings, etc... If anyone from Samsung is reading this, please take note and ask your developers to fix this buggy phone. Thanks!