"Reception" is when a phone, a television, or other wireless device gets a clear signal. When you "get reception", it means that you can connect to the wireless service. You use it like this:
I can never get reception out at my parents' house.
When you continue to be connected to something, you say that you "have reception" or are "getting reception".
When you "lose reception" it means that you get disconnected:
Sorry I wasn't able to call you back earlier. I was driving through the mountains and I lost reception.
"Reception" is an uncountable noun, so you should not use "a" with it, but you can use "any":
I'm not getting any reception at all.
A similar phrase to "get reception" is "get a signal".