Problem with Node Red Docker Synology

Hello everybody,
I have a problem in Node-Red. My home assistant runs on a Synology in Docker. I installed Node-Red as normal via home assistant via add-ons. If I now insert a node and double-click, I get a lot of error messages, namely “you probably haven’t applied science adding a server. Do that for autocomplete to work” "cannot get / home-assistant /% 25% 25ID% 25% 25 / services “OR” cannot get / home-assistant /% 25% 25ID% 25% 25 / entities "

I pressed “deploy”, I restarted, I restarted HA. I reinstalled node-red but it didn’t work. Does anyone know any advice for me?