Hosted Feature Layer arcade expressions

[SLouq]

I have a copy of a hosted feature layer which I created to hold points and calculate elevation values taken with a Trimble R2 unit. The feature layer was working as intended but it wasn't showing me real time elevation values on the tablet as I had configured it to. I decided to try and edit the Arcade expressions which calculate the elevation values to see if that would make them appear in real time on the tablet out in the field. 

What I didn't expect is it also changed the name from 

MSL (FT) {expression/expr0}

MSL (M) {expression/expr1}

HAE {expression/expr2}

to 

How can I revert the expression name back to the original?