m0useanswered grow question a year ago You have to add the photos to any week n hit save, then it will ask you to pick a new cover photo of the ones in that week your editing, you can edit any week.
If the popup is not happening disable any popup/ad/script blockers
After its assigned as your cover photo you can delete it n just hit cancel when it asks for an update cover photo pick, it will keep the old one you just removed.
Sometimes it take acwhile for gd to update cover-photos., the sites not 100%
Good luck!