Flow between vibrating plates

Hi,
Brief intro about my project:
Two asymmetrically walls, create a channel that can rapidly open and close. Water rushes into the channel when it expands and is forced out when it contracts.

I am trying to vibrate two walls up and down in fluid structure interaction by defining
solid mechanics->prescribed displacement and then i assigned two prescribed displacement values for both up and down wall.
But when i try to run my model i get error saying maximum number of newton iteration reached and non linearity can not be solved.The relative error is greater than the relative tolerance.

Could you please help me here?