Thanks! This worked for me - somewhere along the way Instagram asked for new details to move back over to professional. Once I filled the details in I got an error message something like “this can’t be completed now” (I can’t remember the exact error message) at this point I just pressed next and it was able to move on to the next step. Just adding that here in case someone hits the same speedbump
PS I had a FB/Insta store and it disappeared (this is because FB removed stores unless you upgraded to in-app checkout). Now that I’ve got it back again I’ve noticed that the collections on FB/Insta no longer sync with those on my Shopify. So the collections on FB/Insta shop have to be manually filled with products : (