You can adjust the level of your training program to start over or simply level down if you feel the app moved you up too quick.
Go to Settings > My program
Tap on your current objective (Ex: Objective 2 - Basics of Contraction Quality)
At the bottom of the screen, you should see a card
Tap it to level down
On the pop-up window, choose the level you want to go back to
Confirm
Et voilà
You can go back to training normally, the new selected level will be played.
⚠️ If you’re at level 1 of objective 2, you cannot level down to the first workout. To retrieve content on how to use Perifit, see here