Welcome to Private Flying and PPRuNe!
Agree with what others have said. Don't worry about it. And don't worry about re-scheduling either. Just book lessons twice a week, and "know" in advance that you probably won't fly half of them, especially during the earlier stages. It's something you'll have to get used to, I'm afraid, because it doesn't change even after you finish your training and get your PPL.
Unless you get an IMC rating, of course
FFF
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