@Stephanie77 There are a number of reasons this could be happening and without access to the gradebook all one can do is guess.
-Is the student's Course Grade manually overridden? The gradebook will not calculate those.
-Is the Assignment or Score marked as Exempt?
-If you are using Category Weighting, is the assignment in a Category that is part of the weighting?
Screenshots of the assignment and grade setup are helpful. Be sure to redact live student data.
@Stephanie77 I should have asked in my original response--is this in reference to PowerTeacher Pro gradebook? Is the assignment set to count in the Final Grade (see screenshot)?