As far as I know a photo purchased for calendar use should be bought as extended license. However I have a photo that was used in a wall calendar that was only ever bought as standard license. I'm sure the company who did that purchased it through Adobe Stock because they credit it on the back of the calendar.
Question is who do I send this information to (photos of calendar and company's name) I can't seem to find an email for this on Adobe site. Or should I just contact the calendar company directly?
Yes, you are correct. Calendar images require an Extended license. Please open a case via the contact us page found at the bottom of the Adobe Stock Contributor Portal with all of the relevant information and we will look into it.