Breastfeeding help

My baby keeps pulling away from my breast and then cries because she wants it back so I give it to her and she pulls away again and does that for a while. It takes me around 3 hours to put her to sleep. She had her 2 month appointment earlier this week and I mentioned it to the pediatrician and she said she couldn't find any thrush/yeast infection. She did mention that she seems to have a tongue tie. Can a tongue tie be the cause? Does any mom have a baby that acts this way? Any advice would be appreciated. She's been acting like this since she was a little over 2 weeks old.