SIM800L not connecting to mobile network

Hi,
I want to control my Arduino via mobile network with a SIM800L EVB module. I do this with AT commands and software serial.

But there is no connection to mobile network.

NET led is flashing about 10 times (searching for net), then both NET led and Ring led are off for about 1 second (looks like reboot) and then again 10 time flashing NET led.

It seems, there is no connection.

This is what the SIM800L says:
> AT+COPS=?
Call Ready
SMS Ready
+COPS: (2,"E-Plus","E-Plus","26203"),(1,"D1","TMO D","26201"),(1,"vodafone","voda D2","26202"),,(0-4),(0-2)
> AT+COPS?
+COPS: 0
OK
RDY
+CFUN: 1
+CPIN: READY
> AT+CSQ
+CSQ: 0,0
OK
+CPIN: READY
> AT+CCID
8949xxxxxxxxxxxxxxxf
OK
+CPIN: READY
> AT+GSV
SIMCOM_Ltd
SIMCOM_SIM800L
Revision:1418B04SIM800L24
OK
+CPIN: READY
> AT+CBAND=?
+CBAND: (EGSM_MODE,DCS_MODE,GSM850_MODE,PCS_MODE,EGSM_DCS_MODE,GSM850_PCS_MODE,EGSM_PCS_MODE,ALL_BAND)
OK
+CPIN: READY
> AT+CSCLK?
+CSCLK: 0
OK
+CPIN: READY

Sim card has no pin. Sim card itself works fine with 3G- and old 2G mobile phone.
I use 5V PSU with 2,5A max current, so this should not be the reason.

Has anyone an idea how to connect this SIM800L to mobile network?

Thanks.

I believe some of those modules have an inadequately specified capacitor on them; you may need to replace the capacitor.