Need help with LVNV Garnishment for unidentified debt!

I live in the state of Georgia and just received via certified mail garnishment paperwork on behalf of LVNV Funding LLC. These are copies of some of the paperwork sent to State court of Gwinnett County. It was sent from a John P. Farrell who is the attorney on behalf of LVNV Funding LLC. It looks like I received copies of his letter to the Clerk of Courts, Affidavit of Continuing Garnishment, Summons of Continuing Garnishment, Answer of Continuing Garnishment, & General Civil Case Filing Information Form (Non-Domestic). I see from reading past forums on there that LVNV Funding can be shady in their collections and I should be aware before admitting to or even contacting them direct. I’m not admitting to this debt by any means but if I had a guess to what it MAY be from, it may be from a past credit card that my now ex-wife took out in my name without my knowledge or consent and racked up countless debt by purchasing Rx meds illegally. We were legally married at the time this took place but this was not and is not debt I consented to. My questions are: 1) What is the best way to find out where this debt is stemming from? 2) How long before they will garnish my wages or what can I do to postpone this from happening while I dig to find the source to dispute? 3) How do I dispute the charges? I have no idea what card this came from so I have no idea even how old the account is. A best guess would be about 5-6 yrs old. 4) I don’t see anything on my credit report in regards to this matter but am in the process of running for all 3 agencies. If I do find it listed on my credit report what should I do? If it’s not listed on my credit report, do they even have any ground to garnish? I basically need to know the best steps to go through trying to identify the debt, stop this garnishment in the meantime, and dispute the charges. I appreciate the info.