How to get tier/plan name?

We have integrated Amplitude (beyond the basic integration) and we need help in one specific issue - we are not able to get the tier name of the currently logged in user.

plan.nickname returns only monthly or yearly - instead I need something that returns the name of the tier. Is there something like that available?

Is there a place in Stripe I can edit to change the ‘Monthly’ or ‘Yearly’?