Mine is doing the same thing. The evaporation is so bad that it has damaged my cabin filter twice now. When standing in traffic I can smell the evaporation inside the cab. I am extremely pissed off because it has taken 2 years for GM to even acknowledge that there is a major problem here. There is no fix for it. When I bought my truck I was told, if your vehicle had to be in the shop for more than 3 days I would get a loaner. Apparently they don't have enough loaners to keep up with all the new crap they have put out. My 2018 silverado 1500 was worse. Ticking lifters and a transmission that kicked like a mule. I should have sued GM then but I gave then a second chance. That was a huge mistake. Now I have to spend money I don't have on a rental to get the diagnostic submitted to GM even though there is no fix. Check your cabin filter and you will see were all that condensation is going. My truck is less than 2 years old and I'm on my 3rd filter. These filters are not cheap. If anyone knows a good lawyer send them my way.