A fault with the signalling system at Amersham means the line is blocked. As a result of this, trains between Rickmansworth and Aylesbury Vale Parkway may be cancelled or delayed by up to 40 minutes.
Disruption is expected until 18:00.
Check before you travel:
You can check your journey using the National Rail Enquiries real-time Journey Planner.
âââââââCompensation:
You may be entitled to compensation if you experience a delay in completing your journey today. Please keep your train ticket and make a note of your journey, as both will be required to support any claim.