Train services between the East Midlands and London have returned to normal after a day of cancellations.
The union has not ruled out strikes
No Midland Mainline services ran on Sunday because of union negotiations involving drivers.
The talks have stalled but the ASLEF union has said it is ready to meet the firm on Tuesday to try and reach agreement on a pay deal.
Company bosses have apologised for the disruption and refunds are available for those who booked tickets.
Drivers also voiced concerns about extra pressure caused by new services between London and Manchester and disruption due to work on the Eurostar terminal at St Pancras.
Throughout Sunday, passengers arriving at Nottingham and Leicester faced a long journey to Grantham or Peterborough if they wanted to get to London.
Those at Derby were forced to travel via Birmingham.