I just reviewed your order history, and don't see that you purchased 2880 carts or a 2880 resetter from us (unless maybe it was under a different name/account?).
Without knowing which carts or resetter you're using, the age, etc... I can tell you generally if a resetter used to reset a cartridge chip, but now doesn't, then it may be the cartridge chip or resetter that's worn out, or they're not making a good connection. You can test the resetter on a different cart/chip, and if it works correctly, try it on the first cart again, and if it still doesn't work on the first cart/chip, then I would suspect that chip has worn out and can no longer be reset. With our refillable carts, they can be refilled/reset many times, but we recommend getting a new set every year for the best results.
I hope this helps, best regards~ Dana