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First, law firms qualify as third party collectors, and are thus bound by the FDCPA.
Did they provide you a dunning notice in their letter to you?
You can immediately DV them, even without dunning notice or posting to your CR. That will preclude them from making a post to your CR until such time as they respond to your DV letter. I would NOT call them under any circumstances!
The date you "last paid" is irrelevent. What is the date of alleged first defauilt (DOFD)?
I would respond to them only by way of a DV letter under FDCPA 809(b). There is no need in your DV letter to mention expiration of the SOL, for that has nothing to do with the validity of the debt, thier ability to attempt to collect it, or posting to your CR. Expiration of the SOL is only your legal defense should they bring action in court, and has nothing to do with collection or credit reporting.
Shut down their collection activities by sending them a DV letter. If they have dunned you, make sure you do this within 30-days.
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