I ordered fly papers from Amazon.
16 in total but have have only hung up 4.
One has no flies. One has a couple including the one I ‘chased’! One has a a fair few and one is covered in them!
I still have 2 or 3 flies but the fly papers or at least one of them seems to be the best method!
Disposing of them is going to be grim as just looking at the one that’s attracted the most makes me heave.