API error: user does not have access to leads
When retrieving leads from the API in some cases, I get an error: "API User does not have access to leads". I get this with both the v2.1 and 2.2 API, when trying to do any API calls related to leads (such as GET LeadStatuses, LeadSources, etc)
When using my own (developer) credentials this does not occur, but I'm running into this issue when trying to authenticate our integration on behalf of a customer.
I tried to reproduce this using my developer credentials by turning off lead management, as well as some other settings which looked like they might be related, but I couldn't reproduce the error.
Does anyone know what permissions this error message is referring to? Is there a specific privilege level needed to use leads? Could this be caused by lead management being turned off, perhaps, even though turning it off in my portal doesn't produce the error?
Anyway thanks so much for reading -- and in advance if you're able to shed any light.