wireless trigger fires fine with the RP but not with R5?

[CarboFibe]

Hello,

I'm working with a Neewer QPRO-C TTL wireless trigger for Canon, it'll fire fine on the RP but not the R5. In the menu "Flash Firing" it's greyed out and gives this message: "Not available because of the associated function's setting. - Shutter mode" This also happened with a Profoto trigger if that helps. 

Regardless if the trigger is attached to the hotshoe and powered on makes no difference, the Flash Firing menu is always the same.

Any help will be greatly appreciated. 
Thank you.

[deebatman316 · Accepted solution]

The flash will only fire in mechanical mode or Electronic First Curtain. Not the fully electronic shutter. 

[CarboFibe]

Thank you so much, I'll try that right now.

Works like a charm now, thanks again.