Save for web - Write permissions error

I am having trouble in Photoshop when exporting using the Save for Web feature ( I want to be able to export utilising slices)

I encounter the following message "Could not complete this operation. A write permissions error has occured" regardeless of where I export it to; internal, external or cloud storage on my MacBook Pro. (Sonoma 14.5, 2.6 ghz 6-core, Radeo, Pro 560X 4 GB, 16 GB DDR4)

Quick export as png and export as png work as expected (although I cannot export slices as far as I can tell using these methods?)

I have also ran through the permissions as outlined at this page and all are correct Basic troubleshooting steps to solve problems and issues in Adobe Photoshop

Thanks!