Video glitching/repeating sections after export

I have been using canva pro for years.

After I export a video, it repeats sections/glitches/loops in parts of the video (see screen recording).

When I'm editing the video in canva, it doesn't show these glitches. Only after exporting.

I've tried:

- using the old editing timeline

- using the new editing timeline

- using a computer

- using the app

- using 'secret mode' on my phone browser

- clearing cache

- starting from scratch and recreating the video again

- using other video clips/uploads

- using another network

Canva support can't solve it.

Help 😭