Errors to find a solution ( Maximum number of Newton iterations reached )

Hi

Im in the work of building MRI gradient coils. Now working on 3 pair of maxwell coils carrying current opposite side. I have built the model and the computation is not succedded.

i get the error

"Failed to find a solution. Maximum number of Newton iterations reached. There was an error message from the linear solver. Maximum number of intermediate iterations reached. Returned solution is not converged. "

and to reach this error it takes abnormally long time.

any idea how to sort the error and to calculate efficiently ( if possible ) . Not all parameter steps returned.