There's a reset which involves turning the key on and off multiple times (I THINK it's on, wait for the dash lights to go out, off, count to 7, repeated 4 times. Do check though) which should clear it, then if it comes back on you know you have an issue.
My airbag light came on when a water bottle rolled under the seat and hit the connector, did the reset and it was fine afterwards. The bottle had momentarily caused an issue somewhere, but not actually caused a genuine fault. It's never come back on after I did the key reset.