I'm going to my bjj gym, but they need parents

I always wanted to do Jiu-jitsu but the gyms i know is very far and some are expensive. But i found this gym that is near to the mall i always go to in holidays and it's free every Friday, i chatted with the owner of the gym, i asked them "am i allowed even if im 15?" They said "yes, but parents are needed." I hope it's simple as that but my parents are busy always go to work and I don't want to disturb them going to the gym.

Should i just call them and let them talk to my parents on the phone?