Maybe it's related to them fixing WoF spins and caused a spike in hCaptcha requests.
Here is more info from hCaptcha faq:
An alert is displayed on the hCaptcha checkbox when an organization exceeds the volume limits defined in their agreement with hCaptcha, is notified, and does not resolve this after receiving notice.
When a company does not adhere to our Terms of Service regarding traffic quotas, we first attempt to contact the organization privately. If an organization fails to respond, their account is flagged, and a warning message is shown. Repeated violations can result in suspension of the organization's account.
If they disconnect them from the service, freebitco.in will only be usable for playing HI-LO, and the fix might take weeks. We can only keep our fingers crossed that another issue won't arise this time