emails home page open extremely slow, send and receive are extraordinary slow

When I open up my emails in Thunderbird, it takes hours to open the home page, most of the time it is a blank page/screen. When lucky, I can see my email home page, however, sending and receiving are also very very slow and take long time to send out and receive. I tried to compact folders, but the screen remains blank and loading of my account page never opens thus I am not able to do any edit or change for my email account in Thunderbird.

Can someone help me solve this problem? Kan Cell Phone: [redacted phone# from community support forum]