The WIFI signal is dropping. What could be the reason?

Question

WiFi

Router Mikrotik hAP lite TC RB941-2ND-TC. The last two weeks the Internet sags, it can disappear for a minute or two. In the settings, it shows that the signal is low. I tried to change the Frequency settings in the settings - it helps but not for long.
What could be the problem?

Answer 1

A neighbor turns on the microwave, a poltergeist flies by, another neighbor distributes porn and a million other reasons for changing the radio.

Answer 2

1) A neighbor also bought a router and now you have a competition, who has more power.
2) The neighbor's microwave is leaky and now, when she is heating dinner, you are sitting without communication.
3) A radio amateur, signalmen, military, etc with a vooooot tamed transmitter / radar / jammer wound up nearby