Cannabinoid tolerance is a real thing. In my personal experience, I've found it's more pronounced and occurs faster with 'THC' but also is a factor with its cousin, 'CBD.'
Is your regular dosage not cutting it anymore? Take a tolerance break! Take a few days off from all cannabinoids, drink lots of water and then do a whole reset. Start back with half your regular dose and slowly increase until you're feeling your normal amount of relief again!