Hi @morlock , many many thanks for your answer.
I already had configured your Phase1 parameters, but I've tried IPSec advanced and gateway ones and It works properly!
I've tested different lifetime values, 1hour, 8hours, 24hours... and it seems it works fine!
Now I'm going to test if it only depends on IPSec advanced "make-before-break" parameter, just to understand what was going on.
I'll provide feedback again.
Many thanks mate!