My Nexus 5 is showing No SIM Card error when inserting a Tata DOCOMO SIM (Service Provider - India). But when I use an AIRTEL SIM it works perfectly. Also, I took the DOCOMO SIM and put it in a Moto X mobile and the SIM was working fine. I am totally confused whose problem is this now. My Nexus 5 or TATA DOCOMO (Service Provider)? Any help?