Locked changing rooms

Hi mums and dads of Reddit.

Ive got a 10 week old and have been venturing out of the house more and more. I’m based in London and keep running into the issue of locked changing rooms, particularly when they are combined with the disabled loo. I was surprised that I even had this issue at my favourite museum, and ended up changing her in a corridor because LO was losing her mind and I was miles from anyone who could help.

Is locked changing rooms normal? Is it worth me getting a radar key as I’m out and about at least 3/7 days a week?