Hello @Maisa
Thanks you for your kind reply. May I ask you if you had tried it with a Shedinja ? It is this particular pokemon that provoked the bug. I have indeed selected the yes option, once, then it debitted the 15K from me. Seeing that Shedinja still didn't have learned the move, I tried again and the same happened.
Let me know should you need anything else !
Best,
Cédric