WE310F5 HTTPS connection [closed]

I'm trying to establish an https connection to a server using the telit we310F5 module.
Is there a specific sequence of commands needed to make it work? do I need a specific way to store the CA root on the module (i'm thinking about the special characters inside the CA)?

The sequence i'm now using is this

loading certificate

AT+NSSLCERTSTORE=0,1,1,"cacert",<len>,<certificate PEM>

Verify certificate
AT+NSSLCERTLIST=0

Connection

AT+NHTTPCINIT=1,100,1440,1440,1440AT+NSSLCFG=<cid>,2,"cacert"AT+NSSLCFG=<cid>,9,"1"AT+NHTTPCCO=<cid>,"<url>",443

i get all "OK" responses, only the last command (open connection) gives me ERROR

Where is the problem?

Thanks