Sorry I have no pictures and not willing to remove the battery as I have to fix the problem then again,

But try to explain it better:

When my phone started to had the problem I saw that after replacing battery it did not asked me for the SIM card code.

After removing and inserting sim card again it asked for the number but after the last digit and ok it took a very long time to show the error message.

Next step was to push the 6 connectors a little bit up with a piece of paper I put under the connectors. Insert SIM card and battery and the phone started normal and showed the network connection. After a while I lost data connection which came back.

Shaking the phone and the error came back.

So I removed the battery again and but a piece of tissue paper first on the place of the outer 3 connectors that the battery is pushing the sim card harder against the connectors but still same issue.

I move the piece of tissue to the inner connectors and insert battery again and since this the error is gone and the phone works since this without problems.

The problem seems to be the connector which connect to the SIM card. All 6 seem to need a good connection. As your problem may be another connector as mine you just have to try.