Can't export full .pbix + can't publish after live connection workaround

Hi community,

I've been running into a frustrating chain of issues over the past few days and wanted to see if anyone else is experiencing the same.

Issue 1: Can no longer export .pbix with data

I have reports that I've successfully downloaded as .pbix (full copy with data) many times before. Suddenly, I'm getting the error: "We couldn't export to .pbix format."

The only download mode that works now is "A copy of the report with a live connection to the data online" — the full data export fails every time.

For context:
- The report was originally published from Power BI Desktop (not created in the Service)
- Large dataset storage format is OFF
- No incremental refresh configured
- The tables are not large at all, so dataset size shouldn't be a factor
- No deployment pipeline involved

Issue 2: Can't publish after editing the live connection .pbix

After making report edits in Desktop using the live connection file, I tried to publish back to the service and got this error:

"An error occurred while attempting to publish 'Report Name.pbix': The remote server returned an error: (404) Not Found."

My questions

1. Is anyone else suddenly unable to export full .pbix files from reports they previously could download without issues?
2. Is there a known issue with the UK South region affecting exports and publishing?
3. Any workaround to publish a live connection .pbix back to the service?

Thanks in advance, any help or confirmation that others are seeing this would be really useful!