The Minor Injuries Unit at Whitby Hospital will close early, at 8pm, for the second night running tonight.
The Humber Teaching NHS Foundation Trust confirmed the early closure, citing unplanned issues, though the MIU will open as normal at 8am tomorrow.
A statement from the trust said: "In order to maintain a safe service, and having reviewed attendance levels for the MIU, the decision has been made to temporarily close the MIU at 8pm (usually 11pm) this evening. It will open again tomorrow morning as usual.
"The MIU department will have signage displayed to redirect visitors."
Visitors arriving with a medical emergency should press the sign and buzzer next to the MIU front door, which will put them directly through to the Yorkshire Ambulance Service, who will assist from that point.
All other visitors will be instructed to call NHS 111 and seek advice from call handlers on alternative assistance.
Humber Teaching NHS Foundation Trust's statement finished: "We would like to thank staff and the public for your understanding and support in following the alternative MIU guidance and reassure everyone that the Trust is working hard to resolve the issue this week.