HTTPS Get Request doesn't work

[kortos]

Hello,

i try to do a http get request with an https url. In debug mode, i get the following result:

`Testing GSM module For GPRS Connectivity
Should be ready by now
AT

OK

AT+CSCS="GSM"

OK

AT+CMGF=1

OK

AT+CMGL="ALL",0

OK

Device is Attached
Connecting to APN
AT+CIPSHUT

SHUT OK

AT+CGATT=0

OK

AT+SAPBR=0,1

ERROR

AT+SAPBR=3,1,"CONTYPE","GPRS"

OK

AT+SAPBR=3,1,"APN","web.vodafone.de"

OK

AT+SAPBR=3,1,"USER",""

OK

AT+SAPBR=3,1,"PWD",""

OK

AT+SAPBR=1,1

OK

AT+CGATT=1

OK

AT+CIPMUX=0

OK

AT+CSTT="web.vodafone.de","",""

OK

AT+CIICR

OK

AT+CIFSR

100.73.30.57

Connected to Network
Making HTTP Get Request
AT+HTTPINIT

OK

AT+HTTPPARA="CID",1

OK

AT+HTTPPARA="URL",https://webapp.xxxxxxxxxxxxxx/t.php

OK

AT+HTTPACTION=0

OK

+HTTPACTION: 0,603,0

AT+HTTPREAD

OK

Received Info:
AT+HTTPREAD

OK

AT+HTTPTERM

OK

AT+CIPSHUT

SHUT OK

AT+CGATT=0

+SAPBR 1: DEACT

OK

AT+SAPBR=0,1

ERROR
`

What can i do?