Restored purchased app not available

Dear folk

Purchased two apps which are :

https://apps.apple.com/gb/app/mymedia-file-manager-save/id6444236739

https://apps.apple.com/au/app/sam-tv-remote/id838579136

There was an issue with my iphone15 IOS and apple installed a fresh IOS as result all Apps got deleted

When I tried to restore the purchase for MyMedia ,,,,I couldn't find an

option for the restore option and I couldn't find an email for the

developer

While when I tried to restore the purchase for Sam: tv remote,,,,,option grayed out and developer has an email (contact@nstx.io) but he didn't reply yet

Any advise what else needs to be done ?

Thx