Hi @Sale.Favourite_fab, in addition to what @BramKn shared above for Nginx Proxy Manager, can you try updating the proxy_set_header Connection line when using a hand-crafted server block as suggested by @cuman over here? This seems to have done the job 
You could also switch back to server-sent events (this is the technology used by n8n before v1) if you prefer. To do so, you’d need to set the N8N_PUSH_BACKEND=sse environment variable and restart n8n to pick up the change.