Error in Ansys Vista CPD

Good day. When designing a pump in Ansys with a supply of 50 m3 / h and a head of 50 m, everything turns out fine, when I calculate the pump at 12.5 m3 / h and a head of 50 m, the calculation doesn't go and and the program gives an error. Can someone faced with such. I do not understand what parameter is not set correctly. In the attachment, a screenshot of the error and the parameters I set. Thanks to everyone who will take the time to my problem