Impossible to replace components

[TECNOMODEL]

Today I happen to have something strange, in a joint I no longer have the command to replace a component.What am I wrong?

 

[leggera]

It happened to me too, I think because I had done a level of detail.

 

[Matteo Cappelli dis.CAD]

exact, with the active detail level, (and not main) some axiemi-related commands are not available (e.g. adding a constraint)