Zydrate

Potentially you maybe have had an event occur which adds resources.

The issue persists into mid and late game, particularly from minor races whom are immune to influence starbases and do not have any influence area themselves.

This has been a "feature" since 1.3 Random major and minor races alike will claim that I've colonized in their influence, or have a starbase. Despite being far from their influence, and not even having a single starbase at all. There appears to be no diplomatic malus from these messages however they are annoying.