ScotRail has said it is "really sorry" to customers who were affected by a string of cancellations on the Borders Railway on Sunday evening.
Five services between Edinburgh and Tweedbank were replaced by buses.
ScotRail said it was due to the late delivery of new trains, industrial action and the impact of training drivers and conductors.
It said it was working to ensure it could deliver "continual improvements in the coming weeks and months".
The string of cancellation was described as a schedule "collapse" by the Campaign for Borders Rail.
The company said that although the Borders had not received new trains the staff that worked on the route were being trained on other types of trains and routes.
A ScotRail spokesman said: "We're really sorry to our customers who experienced disruption on the Borders Railway last night.
"We did everything we could to keep people moving, which included arranging alternative transport.
"It has been a challenging time for Scotland's railway, but things are beginning to improve.
"More trains are arriving on time than ever before, and everyone at the ScotRail Alliance is working flat out to provide customers with the service they deserve."
- 18 February 2019
- 5 February 2019