Thank you for renaming the topic to better describe the problem I was having which allowed me to search for a solution.

What was the solution?
Turn off the router for couple of minutes and turn it back on.

Hello,

since today I have a problem to download / update a mods directly in the game.

What did you do?
I started the game after an automatic Steam update from 1.1.87 to 1.1.91.
I cannot download / update a mod(s) inside the game through the game.

What did you expect to happen instead? It might ...