Why are real phone calls appearing as spoofed numbers?

[Android Central Question]

I have a Galaxy Core Prime given to me by a friend with Android version 5.1.1. I just signed up for a new plan with AT&T. The problem I've been having is that I haven't been answering certain calls because they appeared to be spoofed. For example, say that my number is (555) 123-4567, I will get a call with a number like (555) 123-2222. I didn't pick up the phone, assuming that it was a telemarketer. Then my friend sent me a text message asking why I wasn't picking up my phone. Her number looked like the above example (that is definitely not her number). So basically, I just realized that I've been ignoring real phone calls from real people and that this has been going on since I got the phone. Does anyone know how to fix this?

 

[B. Diddy]

Welcome to Android Central! That's interesting -- I've been seeing something similar. I've definitely been getting spam calls from numbers with the same 3 digit prefix as mine, but then out of interest (and the desire to annoy the spammer), I called one of the numbers back. I ended up talking to some bewildered elderly woman who was wondering why I was calling. I'd suggest reporting it to your carrier -- I'll try to remember to do the same the next time this happens.

 

[Almeuit]

My honest guess? People reporting it as spam. The database is hosted by Google but goes off the reports of users.. I am sure a good amount take it to be marked as spam. I figure people are probably marking it due to their hate of ISPs so if the call for them was for a "deal" I could see them disagreeing in the fashion.

 

[B. Diddy]

Is your friend's number in your Contacts?

 

[LeoRex]

I try to put everyone I know in my contacts... Telemarketing losers have been spoofing so many local numbers I stopped answering anything with the same exchange as me that didn't have a name.