Re: I am not receiving text messages on my Note 4..
If you were in an iPhone before, they're going to iMessage, not to your phone. (iMessage and "text" [SMS] are totally different things.) You'll have to disconnect the iPhone from iMessage (either search the web - there are many different ways of doing it, depending on whether you have other i-devices - or go to a Genius bar and they'll do it for you). Then everyone who used to text you from an iPhone has to send you at least one text marked as being SMS, so their phone knows not to send you an iMessage (which your phone can't handle, since Apple won't let anyone use their protocol).
If not, bring the phone into your carrier. If voice works, text should work. Technically they're sort of the same thing.