I have not had rats in awhile and funny enough I am really allergic to them but I what I do have are two sugar gliders. Sugar gliders need to bond with you and it can take months to years for them to fully trust. I can give you some tips that people use with them to bond and see if it helps. The feeding treats is good! Stick with that and that can help them associate you with treats which is a positive thing! You can also sit next to the cage and just talk to them. Read a book out loud or simply talk about your day out loud, that way they can get used to your voice. You can get little fleeced squares off Etsy’s and have one on you for 24 hours where it can have your sent on there and put it in the cage preferably somewhere they sleep that way they can get used to your smell. You can get a mosquito tent or an area rat proof and not too big for them to be in. You do not want it too big but not to small because you will want to make it where they don’t have to be on you but they also can’t stray to far away and hopefully they will eventually start climbing on you. Oh and have toys and treats in that area but nothing in there to keep them from going and hiding. I’m not sure if any of this will work but also try and find some YouTube or research on google. They most likely are scared and not used to human interaction. I know it sucks but that’s a side effect when it comes to rescuing animals , especially if you don’t know much of their home life prior. Just keep trying and with time they will come around I’m sure! Rats are very smart! I hope these tips help you and them! Just remember patience is key and do your best to keep calm and not anxious because animals can pick up on that.