My reactions button has disappeared

Hello,

I do not have a 'reactions' button on the bottom of my screen anymore.  It may have disappeared since the last update, but I am not 100% sure.

I am in the middle of a two-day meeting as an attendee.  I have an account through my workplace.

I cannot find a way to indicate a 'raised hand'.  I can submit a screenshot , but I can't see an option to attach it. 

 I use a MacBook Pro, and I believe I was on Chrome today, but I also have Safari as an option.

Suggestions?

Thank you!