Make sure your mobile network/mobile data works correctly. I will suggest putting it in airplane mode, turn airplane mode off, disable Wi-Fi to see if you have a data connection. My Hotspot works fine, just tested it again.
Please try the suggestions made by @Ekamek . If the issue persists, please send us an error report. We apologize for the inconvenience and appreciate your contribution to the beta program.
One UI Beta Team.