Hello jdamps1974,
Thank you for reaching out to Apple Support Communities.
It sounds like you are attempting to make an in-app purchase. These are usually purchased within an app using the App Store to complete payment.
What are in-app purchases?
In-app purchases are extra content or subscriptions that you buy inside an app. Not all apps offer in-app purchases. To check if an app offers in-app purchases before you buy or download it, find it in the App Store. Then look for "In-App Purchases" near the app's price or Get button.
There are three types of in-app purchases — subscriptions, non-consumable purchases, and consumable purchases.
More details can be found here: Buy additional app features with in-app purchases and subscriptions
If the issue persists, can you provide a few more details? Which device and OS are you currently using? Are you currently using the Linkedin app? Also, have you purchased credits before from LinkedIn?
Cheers!