PR pro 2020 Export Issue - become GREEN!!!!?

Hi, I have just installed the PR Pro 2020 version, and the export becomes all green? I've tested the same video element both in the 2017 and 2020 versions, and it works as normal in 2017. So there might be bugs in 2020? Since I also need to use some template, which is above PR cc 2019 version, so I have no chance to go back to 2017. Please help me out ASAP, I have a very urgent case that needs to be completed today. 

Does anyone encounter the same issue?