I've put the AX210 in 3 devices (2 laptops and one PC), haven't had any issues. What issues are you having, low speed, disconnects or something else?
I just ran a test and this is what I get on a anemic antenna through some pretty thick reinforced concrete walls (but this is the best result I get, it goes from 400 to 600 usually).
https://i.imgur.com/73CZ2jz.png
I get double that when I'm right next to the router with my laptop (the result above was from the PC, but the laptops get similar results).
If you don't mind, which manufacturer did you get?
https://www.ebay.com/itm/255098220132
I got recommended this one and as I said I had no issues so far with it.