Workouts completed in the Singletrack Slayer plan are not credited

I have been following the Singletrack Slayer training plan for 6 weeks, and many of the completed sessions were not credited to the plan, although they appear as completed in my activities. Zwift support replied that due to technical limitations they cannot correct this flaw. Additionally, since the training sessions are not credited, I am stuck at level 28, the kilometers traveled and neither the elevation increase.

Can someone help me with this?