Dear Vonn B.,
Good day ,
Thanks for posting in Microsoft Community.
I understand that you have an concern on "Cannot use Clickup Add-in on your delegate user's account whereas it's showing on your own admin account ". Before moving forward, I would like to verify few things to narrow down your scenario.
Would you confirm me whether your employer can use "Clickup Add-in" direct from his / her Outlook client ? its working on his / her side ?
Additionally , As you have delegate access for your employer account therefore you can also access your employer's account by outlook web access.
Steps are : Open your own admin account by OWA > go to your profile > open another mailbox > click on new message from your employer's account and try to check if you can see / use "Clickup Add-in" [ Inserted picture for your reference ]


NOTE : For your security and privacy , kindly don't mention any email address / password or other confidential information.
We look forward to your response. Thanks for your cooperation.
Sincerely,
Amul | Microsoft Community Moderator
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