Not receiving alerts for SMS texts

[scubacat]

For the last few months, I have not been receiving alerts for SMS text messages, but the alerts work fine for iMessage. I'm not getting any sounds or even popups on my lock screen for SMS (i.e. the screen stays black if a message comes through when the screen is off). So I don't even know I've gotten a message until I lift my phone up and the display comes back on. I've missed some pretty important alerts because of this glitch. Any idea what could be going on?

 

[Danno111]

I'm having the same issue with a lot of text messages and other Apps that are set to push through and alert.