I finally found a tip that worked for purchasing Goldlings when the game is not happy!
Temporary Soution #1
If you have encountered this frustrating problem when buying Goldlings
I spent many hours searching for a solution to this problem,
but without success. However, after a thorough search,
I finally found a tip that worked
SteamDB provides a direct link to purchase each package from Steam directly
LINK HERE TO PURCHASE GOLDLINGS[steamdb.info]
This opens your basket inside the Steam store, and you can verify the URL
Restart your game.
Thanks to Sovex66 for his excellent guide, all credits belong to his effort. if this guide helps you, please support and rate it via Steam Community. enjoy the game.