troubleshooting ORA-01722: invalid number error in report

[ry1633]

I'm working on a report in Report Studio with fields from two different views.  Doesn't matter which fields I choose from in either of the views one or the other, but when I combine them I get a ORA-01722: invalid number - and I don't know what field(s) could be triggering the error.

When I use a different package that has both of those same views in it configured the same way (with the same cardiniality etc.,),  I don't get the error.     What are some things I can look at to start troubleshooting?  many thanks, ryan

[Francis aka khayman]

q1. what do you mean when you 'combine' the two view? join or union?
q2. is the second package exactly the same as the one with error? (same joins etc?) is it the same package saved as another name? or was it created from scratch but made in such a way to be exactly the same as the package with error?

[ry1633]

a1 - by combining I meant bring fields from each view into the same report

a2.  created from scratch but made the same way