Hello @Rono, Jacob
Thanks for reaching out!
We have performed this use-case testing from our side.
On modifying SharePoint site URL of a site which is connected to Teams (using SP admin center) and retrieving the same using Graph API gives me the expected results (200 OK) with updated SP site URL in without any delay response.
As this issue seems to be user specific, I would recommend you raise a support case with Microsoft Graph, a Support Engineer will be able to assist you better.
Hope this helps.
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