Some motorists who used the Dartford Crossing over the weekend are still having difficulties paying their Dart Charge following a system update.

Drivers who used the tunnel and QEII Bridge to go between Essex and Kent over the last three days say they’ve been left queuing on the toll service’s website for upwards of an hour trying to pay their fee.

Last week National Highways announced the charge automatic payment system would not be in place for a few days due to improvements being made to the payment system.

Drivers holding accounts were reminded they would not be able to pay their toll until yesterday afternoon.

At the time a spokesman for the agency said: “Starting from 00.01am on Friday, July 28, until late on Sunday, July 30, users will not be able to pay for crossings or access their Dart Charge accounts.

“The whole system is down so payments cannot be made via the call centre either. However, our call centre will remain open to field any queries and offer assurance to customers. Everything should be back up and running on Sunday afternoon.

”When the system comes back up Sunday afternoon, customers will be able to pay manually if they need to. We have given account holders until Tuesday, August 1, to sort out payments.”

However, those trying to pay for their journey and update their card details have not been able to for the past two days.

One person posted on Facebook saying: “Has anyone been having issues paying the Dart crossing charge, I have an account but it’s not working due to the system upgrade. I was told to pay as a one-off, but can’t seem to get through on the website.”

Someone else commented: “Anyone else having trouble logging in to Dart Charge site still seems to be down.”

Another said: “I spent an hour in the queue for the Dart Charge thing this morning - finally got through but it took a while.”

One motorist, who uses the crossing often and has an auto tips account, believes it is people who are trying to pay a one-of-toll that are facing the problems.

He said: “I have an account which auto tips when I go below £10. Because I knew about the system update and I knew I would need to revalidate my payment card I added another £10 to my account beforehand so I should be fine.

“However, I did just try to log on to the website and there is a message which says there is a virtual queue due to high demand for the service.

“It must be because everyone who used the crossing over the weekend is trying to pay for their journey before the end of today.

“I think people who pre-pay should be fine it's the ones who just pay each time they travel who are having to queue.”

A National Highways spokesman said: “The Dart Charge contact centre and website are currently experiencing exceptionally high demand after the system improvements made over the weekend.

“To help ease pressure we have placed people in a queue, which will mean a short delay in accessing the website and our call centre advisors. We thank people for their patience while we work hard to resolve everyone’s inquiries.”