Wifi not connecting easily

My MacBook Pro 2019 16" was diagnosed with hardware problem by an authorized apple service center in Nepal as the wifi was not working at all.

The logic board was replaced with new one and now it is working but there is still an issue:

The wifi connects only when I go within 4 to 5 meters close to the router and after the connection is established, it works normally even if the MacBook is taken to the maximum distance up to where the signal is found.

Is this still a hardware issue or software. Need the assistance.