Have you also checked what is on Equifax and Call Credit for your wife, the three may have different data?
What account did the money that left Natwest go into? Was it a joint account with a debt? If it was an account in your name only then this should never have happened. If it was joint then yes they can get the money from the other joint party to the account via offsetting.
Ask Natwest for a final answer to the complaint, then take it to the financial ombudsman.
We're willing to wipe the slate clean, give you a fresh start. All that we're asking in return is your cooperation.
Just as a slight addendum, financial associations are created on your credit file by virtue of having joint accounts etc., not as a result of marriage. Unfortunately this may therefore have an impact on your wife going forwards.
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