Acceleo in capella

Hello, in fact I would like to know why it shows me invalid, I respect the metemodel of capella here is the line:
[LA.ownedLogicalComponent.allocatedLogicalFunctions.ownedFunctionalExchanges/]
the result :
Invalid
Thanks

Hi Saadan,
Are you just writing this line or are there a line in your Acceleo script before?
LA should be referencing a model element I assume
Stephane