Group pressure after 2nd dive ?

This dive ? Is not giving me the right group pressure after the second dive.
First dive 50ft for 23min surface interval 1:30 then I put the second dive in at 35ft for 46min and it comes up with I but it should be M. Has anyone else had the same problem?

Ccdtdgzhdbdhh about iScuba Plan, v1.2.0