Yeelight can't connect anymore with Samsung Smartthings

I had my Yeelights connected on Samsung Smartthings for a lot of time now almost 4 years. In December i figured out that all my Yeelights are “Offline” on my Smartthings account. I tried to reconet my accounts but I’m getting { “messege”: " Internal server error" }. Any help? I have 40 lights in my home…

Here are the screenshots:

Any help???