Problem with a report based on Union query for comparing row by row

Dear Expert,

Thanks to my application (management of grants: a grant contains general information and is linked to contacts, legal references and portfolios), when an update is done, a new row is entered in the History table for the specific objects.  My purpose was to compare row by row information in order to show the updates.

thanks to the topic Problem with a report for comparing row by row, I solved my previous problem for comparing row by row the GRANT information about contacts, portfolios and legal references with the correct formula. Nevertheless I have a new issue with the report.

I have done another query and a new tab for comparing the general information on the grant (a grant is based on several fields: year, title, description, version, unit, priority area, budget, budget line, remark).  Therefore I created a new variable (of type "Measure"):

Updated General Info GRANT=If( ([Title of the GRANT HIST]<>Previous([Title of the GRANT HIST]))

Or ([Year GRANT HIST]<>Previous([Year GRANT HIST]))

Or ([Version GRANT HIST]<>Previous([Version GRANT HIST]))

Or ([Desc of  GRANT HIST]<>Previous([Desc of the  GRANT HIST]))

Or ([Unit GRANT HIST]<>Previous([Unit GRANT HIST]))

Or ([Priority Area GRANT HIST]<>Previous([Priority Area GRANT HIST]))

Or ([Budget GRANT HIST]<>Previous([Budget GRANT HIST]))

Or ([Budget line GRANT HIST]<>Previous([Budget line GRANT HIST]))

Or ([Remarks GRANT HIST]<>Previous([Remarks GRANT HIST])) )

Then ("UPDATED") Else ("NO UPDATE")

This report is:

In the overview table it is ok:

Now I have to do the same tasks with procurement. In order to do that I updated queries by adding an union. For information a field "Type" exists in the universe in order to know if it's a grant or a procurement. I have created a new variable as previously ("Updated General Info PROC").

It's working:

But I have a problem with the overview report. The values for the general information column are not correct:

For information, the overview table is built with the merged variable (for the fields: Type GRANT, id GRANT, id HIST and creation date).

For the general information cell I have put this condition:

=If([Type Grant]="GRANT")Then([Updated General Info GRANT])ElseIf([Type Grant]="PROC")Then([Updated General Info PROC])

I think that it's a problem of the union. In fact if I reverse the both parts of the union, the error appears for the grant and not for the procurement.

I have tried to do 2 separates tables but it's the same...

Could you please help me to find a solution?

Regards,