unknown call from this number no message

I learned that this number is from a company called:  Level 3 Communications, a "Global network company focused on managed security, network, voice and data services. Access all your needed network services via one provider. "
Another words: a big fat DELETE!

Then you have learned nothing.  Level 3 is a telecommunications carrier just like Verizon, ATT, etc.  So all you have learned is that the number calling you is from their network.  You have not learned the identity of the people or company calling you.