Memrise trying to renew when I don’t want it

How do you contact apple support?

They keep emailing me telling me that memrise is trying to renew my one year subscription and I can’t write them back to tell them I don’t want to renew it and have deleted the app from my phone .

Why do they send emails that do not allow a reply? This is not the good service which Apple usually provides. Thank you for your help and advice.