Microsoft Surface only works with a cable connection?

I charged my laptop last night. Since it was almost full, I unplugged the charging cable. The moment the connection was disconnected, the screen went black and would not turn on. But when I reconnect the cable, it can be turned on and used normally. It is still like that now. The device itself shows that the battery is almost full. However, the problem still remains that it switches off as soon as it is not attached to the cable. Does anyone have any idea what I could do or what the problem is?

I'm grateful for every idea and every tip

I think the battery is defective.