single mom lost income. Credit cards charged off. Same accounts sold over and over

I had a credit score of over 750 three years ago. I am a single mom and I work around the clock.
I had gotton caught up in the credit card circle and my home was hit by Hurricane Katrina and lost all....my credit had gone down due to me not being able to pay the bills...I have many charge offs...of all I finally negotiated with and paid off. So they are showing Charge Off but paid in full.
I had my credit card company sell it to another collector and sometime three to four different companies kept selling it to another...............when I asked for proof of some because I did not remember some..they could not prove it was my debt...only my name and address...do I have to pay them?
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do the debt validation and debt validation follow up
stop the nonsense of repeated same accounts reporting