Connection issue from Datahub on Power BI service

Hi experts,

I've tried to get data from established datahub on Power BI service, but it couldn't work and continued showing "Not Responding." (no error message, just not responding in the window and can't do anything)

Please note the following information:
- data access has been granted
- using the latest version of Power BI
- datahub size is 40MB and 124MB (actually the data size limit for Pro is 1GB, I thought that's far enough for me)

I've searched a lot but found no similar situation.
If any further information is needed please feel free to discuss.
Thanks for the help in advance.