Servicenow Flow Designer not working for other domain records

[AnilkumarP]

1. I have created a flow designer under global domain and Run as Type == 'System User' and this user having proper access.

2. I have to update the records from different domain currently flow designer is not working and record is not updating.

2.1 ->  When we sent mail from external user(i:e my personal gmail) to ServiceNow there is no issue with that it's working fine and record is updating properly

when we sent mail from internal user to ServiceNow it's not working and record is not updating 
2.2 -> Internal UserID domain is equal to == work Item table record Domain, then it's not throwing any error handler message from the flow and it's updating record and working fine.
2.3 -> Internal UserID domain is not match with Work Item record Domain then it's throwing error handler message and it's not updating record

3. Write and Create ACL having proper roles only, but still other domain records is not updating  and record is creating.

Expected Result:

Should allow updating of Work Item Record for all users and other domain users as well 

Kindly please help me

[Mark Manders]

You want a user to update a record that is not within his domain? That's going around the entire purpose of domain separation, right?

But it sounds like you have created an inbound email flow and it doesn't matter if you set it to run as system user or not, because the inbound email flow processes the email as per user access. If a user does not have access to a certain record, it can't update it, even if the flow is set to run as 'system'. That's because all users are only allowed to update records they have access to, and by definition, a user only has access to their own domain.

What you could try is to add a 'run with role' to the flow and check if that resolves it. I am not sure if it will override the domain separation (can't test that, because I don't have access to a domain separated instance).

[AnilkumarP]

@Mark Manders Thanks for your response Yes, using inbound email flow.
I have added roles to that flow as well but still not working and not updating record.

Expected Result:

It Should allow updating of Work Item Record for all users and other domain users as well