I may be doing something silly here so excuse me if I’m being dim
I created a routine that turns on my hall light when I get home if it’s after sunset , that worked fine , but then if I turned if the light off it immediately turns back on because the routine is still running. I naively thought that the routine would only trigger once when I actually arrived at home, but it’s triggering all the time
What am I doing wrong?
I’m sure that’s very frustrating. 
Can you post a screenshot of the routine that’s running? Sometimes tiny details matter.
That could happen if your Routine was also checking whether the hall light is off in its conditions, but it would be better to see the Routine rather than speculating.
Yes the routine does check if the ligh is off, I’ll try it without that condition
You could also try marking that condition as a ‘pre-condition’. That would prevent it triggering the Routine while still acting as a restriction.