GSM 4G WIFI Unlocked AT&T T-Mobile Cell Phone I have put my sim card in the phone but it still says insert sim and i can not make calls or MMS PLEASE HELP

There is a freeze and lock issue with this phone reading the SIM cards. This is discussed in the comments of this YT review of the phone.

BLU Products Studio 5 5 Unboxing and Review 4G Mobile Quad Core GSM...

I don't think so....it does not support CDMA.So once you have unlocked you can swap with other GSM providers only.There are many unlock providers like Prounlocking.com to unlock your phone permanently.

You can get the Unlock code for Sidekick 4G phone at
Theunlockspot.com/sidekick-4g/rs10wp9/ and Unlock it from network lock and use with any Mexican gsm network sim.

Turn off the phone and pull the battery out. Put a small amount of alcohol on a cotton swab and gently try to clean the sim connectors. Put again your sim card e turn on your phone. After that, if the phone doesn't recognize the card, try with another simcard if possible.

What is your Phone Brand and it's Model?
Make sure that your phone has been unlocked....If the Phone Locked means if you insert Other Network Sim card means it says invalid Sim or Sim card error...So find out the Network and country locked now,all network locked Phones cannot be unlocked ,Some Network locked Phones can be Unlocked.It depend on the brand of the Mobile also,you can unlock it using the Unlock code,You can get the Unlock code from the Theunlockarena.com
and Unlock it,after Unlocked the Phone use any GSM Network Sim card,You cannot use the CDMA Network Sim Card in the Unlocked Phone,Only GSM Network locked Phones can be Unlocked...

you need top unlock it while use it for other network , try unlcok codes , if you want to unlcok means try here http://www.wickedunlock.com/

The EVO 4G is a CDMA phone. It is not unlocked like a phone that runs on a SIM card (like AT&T or T-Mobile). It can really only be used with Sprint (probably Virgin & Boost, maybe Verizon eventually), but is completely incompatible with any SIM card or GSM provider (like AT&T, T-Mobile, etc).

try with a diferent card

I guess your phone has not been unlocked yet. Unlocked phones do not have any specific carrier software and work with all GSM carriers. These include T-Mobile, Cingular and AAAA . Multi-band unlocked phones also will work with carriers in other countries.So I guess you need to unlock your phone so that u can enjoy in your country.

Some of the sellers of these types of phone state that MMS and Data services may not work without a chinese sim card