If I turn my kettle or microwave on in my kitchen it will kill any bleutooth or wifi signal. My microwave is getting on for 15 years old, maybe newer ones are better, but the kettle was bought last year.
If you cannot change the microwave, consider trying a different wifi channel. I once had a 2012 Panasonic microwave that killed 802.11g channels 7 and 14 but not channel 0.
I am not too bothered about it. I only use it every other day for about 3 minutes to heat up some porridge. I keep on meaning to buy a new Microwave, I bought it in ASDA 15 years ago for £30 and it just keeps on working.