Hi, I noticed nobody responded, so here’ goes!
If you aren’t shaking the bejeesus out of your nic base, you need to. if it’s in VG, even more so, like between every mix. If you just leave it on the counter and pull from it, you can get highly concentrated pockets of nicotine, called hot spots, but I think Hot Pockets would be better!
If you are shaking well, it could be a bad batch or has been stored in undesirable conditions for too long a time.
Hope this helps!