test mode with real account identifiers

Hello,
I have a problem with the plugin. Indeed, I checked “test mode” and entered the identifiers obtained from my sumup account (which is not a test account). After activation of the payment scope, the plugin works in “test mode” except that the payment was real.

And now when I uncheck “test mode”, it says “Provided credentials are incorrect”. However, these are the identifiers of my real account. Is it because I have already used them for “test mode” that I can no longer use them?

How to fix the problem?

Cordially

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