Hello everyone!
I have got a problem with Umbrello UML Modeller.
I'm planning a Sequence Diagram as in the following image:

But I can't design it with Umbrello. I'm not able to do the activation bar below the firt object to the left (in this case is named "UtenteSocio") that is relative the operation of "visualizzaAbbonamento()".
Exactly when I try to do a synchronous message, Umbrello automatically creates the activation bar only to the right (preciselly below the object "Sistema web") or only to the left (if I do the opposite operation before clicking from left to right), while I would that the activation bars are in both parts (both below the objects "UtenteSocio" and "Sistema web"). Here is the diagram that I get with Umbrello.

So you can observe that in the previous diagram created through Umbrello the activation bar is missed below the "UtenteSocio" object.
Do you think there is a solution to this problem? Would you be able to create the diagram of the first image with Umbrello?
Thank you in advance