MikroTik say that wifi problems are solve in some case what I speak… I not 100% it’s your problem. People write and Mtk answer here: write at post http://forum.mikrotik.com/t/v7-1beta2-development-is-released/142356/1
You can check and confirm that your case is solved by new ros7.1b3 https://download.mikrotik.com/routeros/7.1beta3/routeros-7.1beta3-arm.npk and change log say
What’s new in 7.1beta3 (2020-Dec-02 15:59):
*) other fixes and improvements;
and this other fixes should solving wifi problems… please check.