Can anybody help me with this error(serious comments only)

Today i had build this robot in a workshop. It is to be controlled by phone over wifi with a special app. The thing is, i can control this robot with other phones but it doesn't connect to my phone despite many efforts!! Literally it connects to every other device. Mine is galaxy a55. Can anybody please diagnose the issue there is no issue with connected wires.

Today i had build this robot in a workshop. It is to be controlled by phone over wifi with a special app. The thing is, i can control this robot with other phones but it doesn't connect to my phone despite many efforts!! Literally it connects to every other device. Mine is galaxy a55. Can anybody please diagnose the issue there is no issue with connected wires.