Debt validation sent back with only name and address

I sent a debt validation letter to a debt collector.
Got a return letter with my name, and address as validation.
It was not on any letter head and I responded by demanding VALIDATION of the debt and not verification of name, address, etc.
I gave them 30 days to respond and letter was sent certified.
I have received nothing back.
What and how should I demand that all references to this debt be removed from my credit file
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file a compliant with your state attorney general
call the collector and explain what your are, or have done
offer this debt follow up letter
dispute the credit as fraudulant on your creit report.