Maximum number of Newton iterations reached. in microfluidics model

Hi everyone

I am trying to do a model of solid interaction with fluid in microfluid channel
firstly I set input of inlets by using constant velocity (v)
I could run the simulation so well
then I want to use constant pressure instead so I just change a type of input inside the inlet setting, but this time it shows the error that "Maximum number of Newton iterations reached." even I re-meshed and checked all my physics parameters still error occurs. interestingly I even use the mean value of pressure which I measure from the model thatI could run my using velocity input.

Does anyone have any idea about this issue

thanks in advance
Korakot