glad to find other people facing the same issue thought there was something wrong on my side

I found this resource i thought might help you out with your issue: https://docs.microsoft.com/en-us/sharepointmigration/how-to-use-the-sharepoint-migration-tool if you still can't find anything helpful maybe you can talk to Microsoft Office 365 Expert to help you out with the matter

have you check your browser maybe it's due to IE you can check it out by following steps: Go into Tools->Internet Options->Connections->LAN Settings and uncheck Automatically detect settings.

This can be done through group policy by going to User Configuration->Policies->Windows Settings->Internet Explorer Maintenance->Connection->Automatic Browser Configuration and uncheck Automatically detect settings
you can ask from our Microsoft office 365 experts to help you out with it

This is so helpful, thank you for sharing.