I thought a slow IBTS fan had a different ErC (??) but if that’s the issue, contact support at Aillio.com and start a trouble ticket. They need to supply a replacement fan for you to install. There are threads here that cover this including one from me back in 2019.
The most important advice for installing is to take photos as you proceed so you can find your way back after replacing the fan. And be sure the fan blades are rotating after you attach it to the rubber mount— the fan blades can contact the rubber and stall the fan.