Your membership has privileges.
If you’ve been a member somewhere for a few years, that should buy you some goodwill – a thank you, some forgiveness if something goes wrong, a check-in, etc.
That’s the whole point of membership – being part of something that people care about.
We’ve devolved membership to be “Sorry to see you go.” as opposed to “What did we miss?”.
If you’re building a program that requires membership, start first with what privilege and purpose that builds before you get into email and invoice reminders (those are the easy things to do).