issue with Raxiom Gen5 Tail lights

I have had my Raxiom Gen 5 tail lights on my mustang for over a year now and have been loving them, but I noticed the other night that my right taillight was on while my car was off. I tried turning on and off my lights but the right one would not turn off. I then swapped the right tail light back to the OEM tail light so the battery wouldn’t drain and the OEM tail light shuts off and works with no issues. Right now I have 2 different tail lights on my mustang and I want to put the other Raxiom one back on but I cannot with this issue.