Travisgreentech

I have a 2009 mercedes benz ml320 bluetec 4matic, it has a battery draw that wasn't showing up for me any time I checked it so I subletting it to another shop who replaced a blue key. When we got it back the radio wouldn't work and just had anti theft protection activated see dealer. I have tried resetting it, I have cleared codes in all modules, I have tried to get a anti theft code but my autologic says that may of 2009 production date and later could have an anti theft system in the radio but before that won't and this one is march of 2009. All the codes the from the dealer were 5 digits but the mercedes says it shouldn't have one but asks for a 6 digit. I am currently getting code DA01 and can't for the life of me find any information on it.