Re: " I’m having issues connecting to Apple Pay when I go into my wallet and try to add a card. It says there are no previous cards available and it won’t let me add a new card. Do you know how I can fix this?"
You might want to check whether the OS version is up-to-date with the latest compatible version for the computer or device you are using. Eg: See if an update is waiting to b installed in Settings > General > Software updates. NB Reminder: It is always wise to back up the data before updating OS version.
Else: If OS version is already up-to-date
You might want to try restarting your computer or device (ie: deletes temporary files, re-establishes connections, may update recent changes you have made, and often restores order if something is not working as expected.)
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If more help is needed: Apple Support provides guidance in the articles below:
Set up Apple Pay - Apple Support explains how to add a card to wallet
and
If you can't add a card to Apple Wallet to use with Apple Pay - Apple Support may help trouble-shoot.
or
Apple Pay Support has a website with info. / contact options: Apple Pay - Official Apple Support