I've always found if I use THC for a bit I tolerate/adapt to it. Quit for a week and my tolerance drops back down.
Based on that, my suggestion would be upping your dose to 5 or 10mg of 50/50, or quit for a bit.
Wish that was the case here, I didn't use it for about 2-3 weeks straight when I had my back to back cold, tolerance never moved whatsoever, though it's also not gone up as I take just enough to help me as a sleep aide and not 'get high' if that makes sense. I guess I'm not taking enough for my body to think it's needing to build a tolerance to it?