HELP! Wifi communication problem with Wemos Mini D1 - always cutting out - what am I doing wrong?

Hi, I’m using a wemos mini d1 board for the DIYBMS and have consistent problems with very poor wifi connectivity - the board seems to constantly loose connection, then reconnecting, then rebooting, hanging for maybe 5-10 mins, then eventually it will connect again, give some readings, but then maybe 10 minutes later it starts all over again.

Using; wemos mini d1 (probably a clone) V4 code.

I’ve tried everything I can think of! Different d1 boards, erasing & reinstalling code, just using pre-compiled code images and direct flashing, different wifi routers, wireless access points, removal of all cell monitors, powering the d1 mini from a direct 3.3v supply.

Every single thing I’ve tried still results in the same server connection issues, and losses of communication.
I’ve done this so many times now with the same results that the only thing that remains is to purchase a Lolin official non-clone board.

Just to be clear, I get the same results with not a single cell board connected too.
Help anyone??