Knocking the charge off two BRC 3000mah cells (actually about 2400mah) indicates you are a pretty heavy vaper.
I also vape a couple of 18650 cells into the dirt every day
I would suggest a second charger as two in one charger usually divides the charge current and takes twice as long.
A couple more cells could also be rotated to reduce the abuse to the pair you have.
The BRC 3000mah is a "light duty" cell. Maybe folks will tell you it is a crap cell. It is
cheap, and for me, works just fine for "light duty" applications. Heavy vaping, low resistance vaping, or use in a "Boost" mod may be pushing these cells a little hard.
Sure hope you didn't buy them from a vendor selling them for over $10 each.