Draw mask not working correctly

I’ll be the first to admit I’m still an amateur but I have successfully done simple wipe masks before but now it is functioning in an erratic way. Moving the playhead to where I want the mask to start; I draw the mask, set a control point and then frame by frame move the mask till it’s wiped all the way across the screen. When I play back the clip there is a black box resembling the original mask that I drew but it is in the middle of the starting clip creating a black hole. Once the playhead hits the control point to initiate the mask the subject swipes across the screen but continues to show the masked out clip till it ends and then jumps into the clip that I wanted revealed by the wipe mask. I have even manually keyed in each control point frame by frame with the same results. I feel like I have turned something on/off that is causing this or at least I hope it’s that simple. I have watched every YouTube video and read every manual and “for dummies” book I can find and have been unsuccessful for weeks now. I hope to find some help here. Let me know if there’s anything I can take a picture of to help clarify my issue. Thank you in advance