I’m immune to LSD. AMA

As the title suggests I am vastly immune to most of the effects of LSD. I got 4 250ug tabs (which I know are always underdosed) so I lab tested them with testkitplus and the tabs came around to 60ug each. I took 4 tabs and the total came around to 240ug-250ug in total. But the trip BARELY HIT ME. It felt so mild like I didn’t feel many effects at all. And I know that 250ug is supposed to be a BIG dose when tested for accuracy. So I’ve basically come to the conclusion that I’m mostly immune to the effects of LSD maybe something wrong with the way my brain is wired. The thing is I HAVE tripped really hard before in the past but somehow I don’t think I’m able to trip hard at all anymore. I don’t know why this has happened to me but it really sucks. Can anyone explain this?