problem with the convergence in 2d structure

I have a solid structure designed with 2 plates and clamped with bolts and I have made non linear analysis and my model has converged. And the 2nd time I have made my analysis removing the 3D bolts and using 1d bolts I have made my analysis and it produced fine results and my solution has converged. And this time I want to make my model look more simple and to reduce my computational time, I've designed my model in 2D by using the midsurface of the the model like the 2 plates have been extracted with mid surface and the washers also and the bolt are designed with 1D bolts. My solution was not getting converged I don't know why and I have also specified thickeness to the model and if I use stick condition to model it got converged but not with the correct value and I can't use stick function because in the same time my model has a µ value of 0.18. I've used the contact between is S2S. Can someone please help me to find a proper solution. I'm attaching my model picture to this message. Thank you in advance