Sorry Im in no position to be giving advice just really going on what Bonnie was like..... she was a wee nipper, she would bite hands arms feet but it was mostly just with me and Im the 'leader' type person lol. It went on for weeks and my arms looked like I was a self harmer!
Ive never had a dog before and just thought it was cute playing when she was so tiny but as she got bigger it hurt more and was more of a nusiance so first off it was my own fault she was acting that way as I encouraged it!!!
I tried loads of things that people had said, saying owww loudly etc. I got so stressed out by it and I think that only made her worse. In the end what worked for me was when playing and she started to bite I would get up and walk away from her into another room, totally ignoring her for a few mins, then going back to play.... I did this for as long as it took for to get the message that if she bit then no play. I also tried giving her a toy if she started to bite too.
Hope you get this sorted soon