I would check what the "Grading method" and "Maximum grade" are set for in Scorm activity settings.
Then review what the "Grade Display type" you have for a scorm grade item/column (go to Categories and Items anbd click edit icon). Try displaying it as Real (percentage), for example.
Double-check Multiplicator and Offset columns, to ensure that they do not influence grade calculations.
Screenshots would help to troubleshoot the issue