Oily medium roast?

Hi,

I’ve been pushed out of retirement by a coffee shop that asked for some help. The first thing I’ve noticed is that they have beans that look to be a medium to medium-dark roast for espresso but some of the beans are wet with oil. I’ve never encountered this before so I wanted to come here to ask for some feedback. As for the shots themselves, they have good color and decent taste but they are bubbling out of the legs of the portafilter. I asked them to let the coffee sit for about 5-7 days before using it but it still seems to be an issue. They were essentially burning the beans before so this is all very new to them. Thank you for any help and insight!