thats strange but..
So i change Y position of 2 UIButton via CGRestOffset and all is ok, position is some as you can see.
odometervalue.frame=CGRectOffset(odometervalue.frame,0, offsetYPosition);
units.frame=CGRectOffset(units.frame,0, offsetYPosition);
But when i update title for UIButton units or UIButton odometervalue then offset position is reset for both elements. I cannot understand why.
The answer to this question was to use:
translatesAutoresizingMaskIntoConstraints = YES;
for buttons.
As for the error, it states that one of the constraints can not be satisfied, and that is probably due to the fact that you have moved your button. I do not know sure how to exactly point you to the constraint that is causing problems, but try starting from the constraints connected to the button, and his sub/superviews.