Clash of MAM on Same Tenant with multiple domains

[Psybasec]

Hi,

I have a single O365 tenant with a number of domains on. 

Lets call domain 1 martin@Dominion.com and domain 2 martin@dominion.business

Both domains are registered with O365 and each has its own mailbox for separation/purpose,

I have MAM and MDM setup, using Apple devices with Azure MDM  connectors/tokens / VPP/App Store etc federation to Apple Business Manager of the necessary domains all in place etc) working. 

I can add the first domain to the iOS Outlook client no problem, but, when I try to add martin@dominion.business I get the error message

"Your admin wants the apps on this device to managed with the account 'martin@dominion.com'. The app account you are using 'martin@dominion.business' will be removed. To access your organisation's data with the account 'martin@dominion.business', you must unenroll your device from the company portal."

But its the same portal, O365 tenant. MDM/MAM and AD??

Am I missing something obvious here!!??

[#2]

@Psybasec 

It's not possible to add to MAM-protected mailboxes on the same device, even if they are from the same tenant. Microsoft is aware of this issue.

The current workaround you could do is give mailbox A full access to mailbox B.

Then log into Outlook with mailbox A and add mailbox B as a shared mailbox.

[#3]

@Thijs Lecomte 

> The current workaround you could do is give mailbox A full access to mailbox B.

> Then log into Outlook with mailbox A and add mailbox B as a shared mailbox.

Unfortunately, this did not work... Still get the error message about management...

[#4]

A management profile might still be stored somewhere. Try deleting Outlook and the company portal and try again