Hi Generally recommended ways to eliminate contact convergence difficulties are as follows:
1- turn on the option to know where newton-raphson reseduals are high,
2- use smaller mesh size (this help by reducing contact stiffness)
3- decrease contact normal stiffness, I think its ok to reduce them to 0.1
4- Shorten your time step.
And the last one that is very determining is the type of the contact, Frictional converge more easily
Please send me your contact properties.
Thank you.