Simple view criteria not working!

Simple view criteria not working!

I have a view with the following criteria:

Asset_Owner.contains("WestLB")

Asset_Owner is a multiselect lookup field.

The view displays the error message: We are unable to fetch this data, sorry!

There is another field in the same form called Asset_Scout. It has the exact same settings as Asset_Owner (multiselect, lookup, alphabetical sort, criteria etc.) but references another form for the lookup. With this field as a criteria it works.

A quick response would be very appreciated as I was supposed to send a permalink of this view to a client today.

Regards, Filip