Experiment: asking two questions after someone finishes the course

I'm trying to raise my course price from €149 to €249 and I've been telling myself the problem is the price. But my follow-up is genuinely bad — people finish module one and I never speak to them again. So before I touch the number I want to know whether the churn is the price or the silence. Testing it with the next twenty enrolments: same price, same content, but I send two short personal emails after they finish — one asking what they got stuck on, one a week later offering to look at their work. I'll compare completion and whether anyone asks about a next step.