Cant see my face or share screen on webinar it says not responding

On 2 seperate occassions I have been  granted co host for a webinar. I have never used a zoom webinar before. That being said I was backstage all going well. When it was time for me to go in and i was live. I cant get thru the door. People can hear me and see my name on the webinar  but cant see me nor can I share a screen. It says zoom is not responding. Its def not my internet as previously thought. Why cant I go on live webinar and show my face and share screen. What is happening here. Ive reinstalled zoom and Im updated....?