The concerns were shared on a Facebook community group in which one man had asked if anyone else was “finding they are not getting post” to which many people shared they were experiencing the same.
People in other areas of Oldham and Saddleworth have reported similar problems.
One woman said that she had missed a hospital letter and received it too late, while another said she had received a number of her birthday cards late after a five-day wait between post being delivered.
Royal Mail often prioritises deliveries of parcels as it is logistically necessary to prevent delivery offices from becoming overcrowded and creating a health and safety risk.
The postage service said: “Because of the volume of mail received ahead of Christmas and a spike in sickness absence at the local delivery office, deliveries in Royton took place at least every other day the week before last.
“Our posties worked to clear this backlog last week and service should return to normal this week.
“During exceptionally busy periods like Christmas, it is sometimes logistically necessary to clear parcels out of our delivery offices first.
“Parcels take up far more space than letters, and their sheer number during the festive season means they can build up, block walkways and present a health and safety risk to posties.
“Removing them first allows all mail, including letters, to keep moving and is a necessary part of our planning.”
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However, some residents expressed they had not only experienced issues with letters but parcels too.
One woman stated she had ordered live snails on a Monday and paid for 24-hour delivery but hadn’t received them until the Friday, at which point the snails had died.
Another woman said that she had received a notification from Royal Mail on two separate weeks regarding two different parcels having been attempted but failed for delivery.
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She said she was told that no one was in to receive one parcel but she says she was home and even checked cameras on her home and that nobody came to deliver the parcel.
With the second parcel, she says they also said no one was home which she confirmed but said that she checked the camera footage again and that nobody had been there again, as well as saying the parcel could have fit in her letterbox and was eventually delivered this way.
Around 25 people complained they had experienced the same issues in Royton, with one woman saying she had received no post for more than a week and then received a “huge” delivery.