I and others have had a bug with Elvish Refueler allowing opponents to use it as well as you yourself, but I haven't been stopped from using it myself like you said.
Are you certain it was your own turn and you had not used another exhaust earlier during that turn (doesn't matter if it was on another creature)? Elvish Refueler only allows you to exhaust an already exhausted creature if it is the very first exhaust you do on your own turn.
P.S. if you're looking for a refund you should also use the "reporting a problem in my event" option.
I and others have had a bug with Elvish Refueler allowing opponents to use it as well as you yourself, but I haven't been stopped from using it myself like you said.
Are you certain it was your own turn and you had not used another exhaust earlier during that turn (doesn't matter if it was on another creature)? Elvish Refueler only allows you to exhaust an already exhausted creature if it is the very first exhaust you do on your own turn.
P.S. if you're looking for a refund you should also use the "reporting a problem in my event" option.