I don't understand how the page name changed when you changed the link.... the page name value comes from the pageName that was recorded when the page (with the link on it) was loaded...
Unless you have some customized code that is manipulating the data in a strange fashion that I don't know how we could help with without seeing it...
Now, I assume you are using something like (s_object - https://experienceleague.adobe.com/docs/analytics/analyze/activity-map/link-tracking/link-tracking-faq.html?lang=en)
<a href="some-url.html" onclick="s_objectID='abc';" >
Link Text Here
</a>
to override the link text?
This should only impact the value of the "link" and nothing else...
Can you help explain your current activity map implementation, as it sounds like you have something custom in the mix that could be causing the issue you are having....
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