Caprice bass and Grolsch beer washers

Hi!
I always used these Grolsh beer washers as strap locks, and they never failed at me.

I recently bought a Caprice and they don’t seem to work very well since the strap buttons are different. They tend to go off easily so I need to find a different solution without installing new strap buttons, strap locks etc.
Can you help me?
Thanks.

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