Oxfordshire County Council has been urged to send the bill to repair the incorrect Milton Interchange to its contractor the M Group.
Over 57 hours across the weekend just gone, highwaymen closed the interchange off the A34 for Didcot to resurface the road where many potholes had formed.
But while it opened on time for Monday morning, some of the wrong markings were incorrect.
READ MORE: A34 interchange incorrectly finished after 57 hour closure
New lane markings have been painted on the tarmac of the interchange, but the far left lane going into Didcot has been marked as being the lane for the A34 southbound.
And rather than painting Didcot on the lane next to it, workmen have painted Wantage on the road - a town in completely the other direction.
A spokesman for Oxfordshire County Council said "robust" discussions are taking place to decide who will pay for the repair work.
Ian Snowdon, the Conservative councillor for Didcot, "strongly" urged the council to "stand firm" in these negotiations and ensure that taxpayers are "protected".
He said: "Residents will be rightly frustrated that we are still dealing with the consequences of what has been a very costly and avoidable mistake at the interchange.
"At a time when household budgets are under immense pressure, the last thing local taxpayers should be worrying about is picking up the bill for errors that were not of their making.
READ MORE: A34 'crash' through Oxford causes delays to morning rush hour
"While I welcome the fact that the council says 'robust' discussions are taking place, the principle here is straightforward: if the fault lies with the contractor, then the contractor should meet the full cost of putting it right.
"Accountability must mean something. Public funds are already stretched, and they should be used to protect and improve services for residents not to rectify avoidable mistakes."
He added that "transparency is crucial" and that residents deserve to know how the mistake happened, what safeguards failed and what assurances are now in place to prevent a repeat.
"Most importantly, they deserve confidence that they will not be left footing the bill," the councillor added.
A spokesman for the county council said: "We are aware of the issue and are planning to amend the lining at the earliest opportunity, subject to network management requirements."
Mr Snowdon said work has now been programmed to take place on Tuesday night, March 3 from 10.30pm.
One resident who contacted this newspaper said: "Who actually signed off these incorrect road markings on such a busy intersection?"
Mr Snowdon added: "This will absolutely confuse non-local drivers. How does this happen on a major scheme?"
The work included kerb and drainage maintenance, ironwork adjustments, resurfacing of the existing carriageway and reinstatement of all existing and legal road markings and lines.
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