MsGraph try to read a Shared Mailbox but no default folder found

Question

Hi, I tried to read a shared mail box but im running into an issue:

"The specified object was not found in the store., Default folder Root not found."

Ive searched alot of forms already and tried multple things like specifying the mailbox with name or id but that resulted in a similar error message. https://graph.microsoft.com/v1.0/users/[user_id/email]/mailfolders I think i have enough rights to read the mailbox but it still does not seem to be working correctly. Does anyone have tips or know what could eb wrong?