The biometric program at HMP Isis prison in London requires inmates to authenticate their identities via thumbprint before moving from one area to the next. System errors, however, have been leading to back-ups that leads to all prisoners waiting before they can move on, according to an article from The Telegraph.

A report detailing the problem, which sometimes leaves prisoner movement halted for hours, has noted that if the system doesn’t work for 100% of prisoners otherwise a manual check needs to be performed, which is time consuming and leads to the delays.

While the one-year-old prison was developed with the intention of introducing significant progress and new technologies to the prison systems, the chief inspector of prisons, Nick Hardwick, has warned others not to underestimate how many challenges still lie between the prison and successful implementation of those technologies.

Read the full story here.