You may have a violation of the Fair Credit Reporting Act. However, I would first send one more letter to Experian advising them of the incorrect address. Allow them 45 days to correct it (it should not take that long). If they fail to remove the address, contact a FCRA attorney in your area.
You should consult with a consumer protection attorney. Save all correspondence & envelopes and have an attorney review for possible Fair Credit Reporting Act Violations and/or other consumer rights laws.
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