Hi @debasisbehuria6,
You can ignore this warning message, this is just an information pop. You can not connect your Bolt device to 5GHz wifi network. It can only connect to the 2.4 GHz wifi network.
Go to your hotpot setting -> Set up hotpot -> Select AP Band -> Choose 2.4 GHz band - > Save and then follow the setup process again to link your device to your hotspot network (Click on add network and enter your hotspot name and password.).
Also, check this link Connecting Bolt to College University WiFi Network?
Do let me know in case you need further assistance.