Hey,
please have a look at the forum, especially here: Free plan in an app with a paid tier: license (CC-BY-SA 4.0), personal data and attribution questions
Also, check our ToS at HeiGIT Account, our plans at HeiGIT Account and the following post regarding deprecation: Deprecating "api.openrouteservice.org" in favour of "api.heigit.org"
Best regards