Problem with Multiplayer

[Dom92]

Hello, I have a problem when uploading a self-created card.

First he told me to check my Internet connection. There was only a texture error on the map.

Now the following error occurs when uploading the card: (An unknown error has occurred (code = 7548) or similar. The number is almost always different.

I have already uploaded a card yesterday and this worked but this was smaller.

What do I have to do? What could be the problem?

Greetings,
Dom