Product: Debt collection

Hello, On XX/XX/2023, I received a text message that stated : Hi XXXX XXXX XXXX, this is Central Portfolio Control Inc . Please contact our office at XXXX or online at XXXX  using your AGENCY ID : XXXX. This communication is from licenses Bill Collector. Thank you. Text STOP to unsubscribe. I had never heard from this company at all, so I assumed I would get a letter that explained this debt within the 5 day pay period, according to : 15 U.S. Code 1692g. They did not send any type of validation to this debt within this period. 
I sent a notarized validation letter on XX/XX/2023 via Certified Mail asking for validation of this debt, the name and address of the original creditor, amount, date of original charge off of delinquency, verification the debt was sold, any judgements obtained by any creditor, commission for debt collector if efforts are successful, etc. I did not hear anything until XX/XX/2023, 15 days after the original text. I received a letter via standard mail that only stated who the creditor was, and the amount owed ( I have the original letter and envelope ). The letter was dated for XX/XX/XXXX, however I absolutely didnt receive it until the XXXX, and there was no postmark date on their letter at all, only showing barcodes and my address. In this letter was again, no information about the original address, original amount due, no identifying information for me to try to reconcile this debt. I sent a second notarized validation letter via Certified Mail on XX/XX/2023 again, asking for the name and address of the original creditor, the original amount etc. And I also noted that per the 15 U.S. Code 1692g statute, they were in violation of the law that states they must send a validation letter within the first five days of contact. I also noted that since you have failed to provide me with most of the mandatory information I am seeking, I am assuming that you have been unable to validate the debt and therefore, I consider this matter closed. You may consider this letter your official notification that I do not intend to correspond with you on this matter again. Another note, Per section 15 U.S.C.A. 1692 ( f ) ( 8 ), collectors are prohibited from using any language other than the collectors business address on an envelope, inducing barcodes viewable through a window envelope that could reveal the consumers internal reference number. The first letter sent to me had my name, address and also a very long barcode along with an address and barcode on their return address, again another violation of the FDCPA. 
On XX/XX/2023, XXXX months after the first letter sent, I received the second letter from them, postdated XX/XX/2023, this letter stated in receipt of your correspondence, disputing of the debt referenced above. In response and for your review please fin the attached information related to the debt. If you believe the information set forth is not accurate, or that the debt has been resolved, please send us documentation supporting your position, including payments. Attached is a medical debt that seems to be from XXXX XXXX XXXX. There was no one of the rest of the information I requested, such as the amount the debt was sold for, date of original charge of delinquency, verification the debt was sold to a collector, etc. 
I am unsure of where to move forward, as they have continued to violate the FDCPA in many ways. I would love some guidance on how to go about this. I have all original documents, including envelopes, return slips and the original text message. Please let me know if I am able to submit a formal complaint against Central Portfolio Control, and what my next steps will be. 
Thank you, XXXX XXXX XXXX