Listening to every heart
LoveBug has some good advice. You don't give your ages, perhaps this girl is very young? And her mother has certain guidelines and rules? Are your parents willing to help you see this girl again, perhaps a chaperoned date? There are many ways to work this out, given this limited information. Overall, keep everything you do above board, so that the girl's mother will never be upset or angry at any action you take. Let us know how things work out, or give us some more information and perhaps we can come up with some better suggestions.