Field missing when switching payment gateway

My e-commerce site is live and working properly. I need to change the payment gateway from Stripe to When I make the change, adding in the credentials for Authorize the credit card field disappears from the page and there is no way to complete the transaction.
Anyone else have this issue? Any ideas on how to fix it?

Hi @Sue
I think I had a similar issue a while back and it seemed to be that the gateway API credentials remained saved in the system for the old gateway.
So try going back into the gateway settings in the admin, switch the dropdown back to Stripe, remove any credentials there (this may remove the new ones as well, so keep a copy if needed), save it, and then switch back to the Authorize gateway and ensure the API details are still there (or re-add them).
If this doesn’t work, try clearing all gateway fields (both switching to Stripe and Authorize) and save each - effectively clearing all the settings.
Then delete the Gateway/s (trash can icon at top), and then re-add Authorise from scratch.

Hope that works for you.