Non-uniform pressure along a cylinder

Hello everybody.

It is my fist time working with ABAQUS and I have a problem which I can not understand.

I have a non-uniform pressure (varies with z and theta axis) apply over a cylinder.

The problem is when I run the model, I obtain this error:"Too many attempts made for this increment ". I changed the increment size in the step module, and also I considered the non-lineary geometries, but I obtain the same error.

However if I do the calculation consider a pressure with only variation along the z axis (constant along de theta axis), I didn't have any error when I run the model.

Please, do you let me know if someone had a similar problem with non-uniform pressure (varibility along the z and theta axis)?

我可以欣赏所以μch your help.

Thank you