An error occurred that the shoot button was missing

It happens again and I write again.

Dungeon & Basketball Blitz Event in progress
The error of missing the shoot button has occurred again !!

And, an error that the player became transparent also occurred

The device I am using is an acer Chromebook R11.

In the event that the player became transparent, the round circle displayed on the floor was identified.
Fortunately, we were able to proceed with the event

If there wasn't even that circle on the floor, the event would have just wasted stamina.