This looks like a classical mapping error.
I think that the safest view is that the old right of way is still preserved for the time being. I say for the time being as I do not know what formal legal agreement, if any, you (or your predecessors in title) may have entered into with the council about the public right of way.
If you say nothing about the "new" right of way and allow it to continue unchallenged you may well be deemed to have acquiesced to it after a certain number of years.
Therefore, you could conceivably end up with two extant rights of way over your land !
Talk to the council. It would be better to regularise the matter for the avoidance of doubt and potential trouble in to the future e.g if you wanted to convey some or all of your land in the future or if there was an accident and there was a dispute about responsibility for the accident locus.
Better still, you should talk to your solicitor first so that they can point out any potential problems having had the benefit of perusing the relevant title documents to your property.