did you capture wireshark log in rmnet0 and see if there is incoming packet?
No, I did not. I should have done it.
Now I´m going to try R17-18.6.4, and then I try again with R16 and wireshark
I think is already early to be really happy, but I am pretty sure that my problem is solved.
It was the “route” table.
Althoug I call next function in my code
I think problem was that when I reiniciated my application and the module already had a connection, I did no call this function or something like that and I do not know when that rule is missing. I have to review all my code and see what was exactly happening.
After adding or deleting that rule using the shell, I can connect to my server or not.