Can't get my male to lock

I have a breeder pair of het clown balls and I can't get the male to lock. I had the same problem last year and I tried putting two males in with a female. It worked like a charm with my banana male but the het clown.

Does anyone have any suggestions?

Sometimes it just takes the boys longer to figure out they like girls. A few actually never do figure it out.

I have a 2011 male that FINALLY locked with a female for the first time last year and she gave me a clutch of eggs. Slugs unfortunately but he at least did get the job done.

You just have to try the tricks like rubbing sperm plugs from another male on the female, put a shed from another male in the female's enclosure, pair them the day before a low pressure system (storm) is due, etc.