Re: Valid Address for AFNI
The correspondence address for AFNI Collections is:
Afni, Inc.
PO Box 3427
Bloomington, IL 61702-3427
It's expected that you would have records of your account numbers. If you're getting collection letters, ask the collector for the full account number.
Re: Valid Address for AFNI
In case you want a street address, the one on record with Florida's registrar is:
AFNI INC
404 BROCK DR
BLOOMINGTON, IL 61701
Don't worry about account numbers. They should be able to look up your file with a name and address. There is no required format for a dispute to a collector, except that it must be in writing if you desire them to cease collecting under the FDCPA, but even that only applies in the first 30 days after initial contact.
Otherwise, you don't even have to put the dispute in writing, although it will be up to you to prove you disputed the account. That is why writing is preferable.