Unexpected Error - Power BI Service Dataflow at Editor Page

I am unable to edit or add any tables to my dataflows. The following message appears: 

ApiResponseError: ApiRequest error with status 0
at p.handleErrorEvent (https://asia.prod.powerquery.microsoft.com/MashupEditor/scripts/p.o.a.0405076208ba3af15881.bundle.js:2:26707)
at XMLHttpRequest.<anonymous> (https://asia.prod.powerquery.microsoft.com/MashupEditor/scripts/p.o.a.0405076208ba3af15881.bundle.js:2:28104)

This only happened since last week. I was able to do editing or add tables to the dataflow previously.

May I know if is this related to the size of the data in the dataflow? Because some dataflows with lesser data are able to be opened.

Have seen the suggestion over here: We encountered an unexpected error - Power BI Service Dataflow 
But found no clue. Any other suggestion/solution?

Thanks.