Hey there AaliyahEmma, thank you for reaching out about this. We hate it when our games are black screening, and we would love to assist you however we can!
The first step we would recommend would be to restart your headset by turning it off (Press and hold the power button until prompted to shut down the headset) and leave it off for 10-20 minutes before turning it back on. If the game still gets stuck on a black screen, try un-installing and re-installing the application and give it another go. As a last resort, you could try a Factory Reset if all else fails.
If you continue to have issues with a black screen, please test if any other applications are having the same issue. If it is only Gorilla Tag that is having issues with a black screen, please consider reaching out to their support channels for assistance.
Feel free to get back to us any time and we would love to assist with anything we can!