Help Galaxy S6 Messages won't send despite full bars

[Deleted User]

So idk what's up with metro pcs, but no messages will send or data will send today. Yesterday itwas working fine and I just signed up, but my phone is indicating I have 4g and full bars, but nothing will send when I'm in my office. Can anyone help here, I tried rebooting etc

 

[DirtyDee]

That could just be an APN issue, I would say give that a check then clear out cache

 

[Deleted User]

That could just be an APN issue, I would say give that a check then clear out cache

how would I fix that?