Having a Galaxy phone means a lot in this case, because there are features available for Galaxy devices which are not available to other brands. Such as Bixby routines. 
I’m not 100% sure, but my understanding is that you should just be able to set up a Bixby routine (not a SmartThings routine) to do this.
NFC tags are one of the standard Bixby routine triggers:
You can find some discussion in the following thread:
Samsung Bixby Modes and Routines to trigger Smartthings?
Anyway, someone else will have to confirm, but that’s what I’d research next in your setup. 
Again, this method will only work on a Galaxy phone. For other android devices or iPhones you’d need to start looking at other methods.