problem with power shield sim808

I have an arduino uno card linked with a shield Sim808 and I want to feed it at the beginning I chose a 9v battery arduino uno card was well fed after I press the button (PWRKEY) so that the LED net flashes but the problem the LED starts flashing but after it goes out gold it must always flash for the proper functioning of the sheild I have even added two more looted 1.5 v to have a 12v power supply and it does not work
here is a picture below

Please do you have any idea about this problem

Disconnect the arduino, try supply only the shield, push the start button and see if the net light start blinking.

same problem

check your SIM card, remove the password, or connect a GPS antenna.

i think the problem is not from the SIM CARD because it work with electricity

Perhaps your battery is empty because I'm testing with the same 9v battery and the shield get to the network normally.

Which 9V battery?
The small PP3 style batteries will maybe last a couple of hours if at all.
They can’t supply the current needed by the shield + Arduino for any meaningful period.

enizar:
at the beginning I chose a 9v battery arduino uno card was well fed…

I have even added two more looted 1.5 v to have a 12v power supply and it does not work

That shield runs internally on 4.2volt, and the datasheet recommends a 6-9volt supply.
9volt is already the top end, and 12volt could well damage the shield.

A SIM chip draws about 2Amp when transmitting.
That supermarket quality battery pictured can only deliver <10% of that for a few minutes.

Try a 6-7.5volt source made from quality AA batteries.
Leo…

OP, Nobody is suggesting you need to increase the supply voltage... What you’re looking for is ‘current’ (not a raisin).

Power - what you’re short of is volts x amps.

In most cases, adding volts can be painful, while adding ‘amps’ is adding capacity to deliver those volts.

thank you the problem was in the battery I changed another battery and it worked well