First click on gallery image, opens and closes

Hi, I´ve installed a Gallery in my pago and the first time that you click on one of them, it opens in light box and closes. From the second time, it opens normally.

You can see the issue in:

https://www.lenasricosan.com/nuestra-fabrica-de-lena-en-el-espinar-segovia

(I´ve tested the same gallery in ohter web page of mine and the behaviour is the same)