My six month old female kitten bites me! She doesn't do it hard, and since we have had her (12 weeks old) she has done it, so every time she bites I put her on the floor and / or walk away. She still doesn't stop though, and even though it doesn't hurt, she kind of nibbles, it is really annoying. This morning my husband left the bedroom door open and she jumped on the bed bit my chin, my elbow and three of my fingers. The thing is a lot of the time she is purring while she does it, so I think she is being affectionate but it's still annoying! Her brother, who we got at the same time, has never done this!
I've got a lovely 10 yr old female cat, who's always been a "nibbler". Sometimes, it hurts like hell (basically, when I ignore her initially!), but, like yours, she purrs when she's doing it, and I think she's just being (overly enthusiastically) affectionate! None of my other cats do it, but I'll put up with it, because she's not being nasty or vicious and I love her to bits!! I know this won't help your situation, but at least you know you're not alone!! K xx
I've got a 6-month old monster kitten that bites. I've tried the same as OP, but he still does it. I do love him though, so I forgive him! He's a lovely cuddly little kitten when he wants to be, just lays in my arms and goes to sleep.