Greetings of the day,
Based on the error message provided, we have found the error is from MFA services which are automated and cannot be translated. And unfortunately, there’s no out-of-box solution to modify these messages currently. This is the reason why you cannot find these messages in Localization IEF file. We are really sorry for the inconvenience. I would suggest you provide your ideas and feedback in the following link.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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