I had this problem with my mi box s and also mi tv stick recently. Go to wifi settings and choose static IP. For some reason DHCP has problems with some routers. Once you do the static, internet will be rock solid and won’t drop ever. Try it.

Make sure your router GATEWAY and IP settings and also DNS settings are correct. It will work if all the info is entered correctly.

Yep. The gateway id is the router access as per your picture there. The ip you can assign according to the one in your mi box. DNS you can use 8.8.8.8 primary and 8.8.4.4 as secondary.

r u using mesh wifi? my km2 also have wifi issue, took me 1 hr to figure out what is wrong (totally cant connect wifi at all) the culprit is fast roaming for deco mesh. once i turn it on my wifi confirm disconnect. so right now i just leave it off for the time being and my wifi no longer have issue.