Save for Web - Animated GIF Export Error

When I try to export an animated GIF through 'Save for Web' I get the error msg 'Could not complete this operation. A write permissions error has occurred.' I'm on the latest version of Photoshop 2023 (v24.0.0  and my Mac is on Ventura (13.0). But I've had an error msg whilst performing this operation on older Photoshop versions, older OS versions and even on other Macs.

It doesn't necessarily happen all the time, but when it does happen it's normally when I have loads of display banner GIFs to export for a deadline.

I've tried different file names, and different locations but nothing seems to work. How can this be fixed?

Thanks