Hi aLEX589741,
Welcome to post in our forum.
Would you please tell us did the issue only appear on the specific client?
If the issue only appear on the specific client, please try to delete SFB cache and make sure it has the latest update, then test again.
If all internal users had this issue, it may be something wrong with SFB server side, so first make sure your SFB server with the latest update and then you could check if there are any event IDs in SFB FE server
Moreover, you could try to use Microsoft remote connectivity analyzer check if there are any errors
https://testconnectivity.microsoft.com/
Regards,
Alice Wang
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