Thanks so much for pointing out the right direction!
I have created a staging website and have figured out that it is my Theme, blocksy, causing the problem.
I will reach out to them for further solutions.
Thanks for your help again.
Big LOVE.
Thanks for your reply.
For my status report, you may find the link via: https://pastebin.com/nK5hLQ63
for my fatal error logs, I cannot find any related to import at the moment.
