Informant error creating bound ticket

[Soporte Informatico Irura]

Hi everyone, i need some help.

Since a time ago i can not be able to save (create) a bound ticket from another existing one.

I create it selecting bound ticket, create bound ticket...
and when I go to save it, Jira shows an error saying "There were some errors creating the ticket. The informant is mandatory" but in ticket creation form there is no field for Informant.

User is manager for some products and groups, of course in which we want to create a bound ticket.

thks in advance.