I have to re-restart my router everytime i want to connect the wifi?

This week, i've tried to connect the wifi in my house, but i wouldn't connected. then I tried to restart the router, then the wifi on my mac suddenly connected. but once it's disconnected, i have to re-restart the router. the other pc and smartphone doesn't face any problem with connecting the wifi.

I have to re-restart my router everytime I left my mac for more than 20 minutes, because its disconnected automatically.

i've asked on other forum, someone told me that there's trouble with airport wifi card. (then he just told me without any solution 😟

First, i thought this is the router problem, till i realise that the other gadget on my house doesn't face this problem.

i've tried to diagnostic, but nothing happens.

anyone can help me?

Thanks in advance!