There has been a "sharp rise" in the number of people not turning up for vaccination appointments across Swansea Bay.
In one day alone this week, 60 people didn't attend their appointments at the mass vaccination centre at the Bay Field Hospital.
Swansea Bay University Health Board explained that vaccination staff stayed late to use up the spare vaccines which had to be used that day or thrown away.
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A statement issued by the health board read: "We have experienced a sharp rise in the number of people failing to turn up for their appointments at our mass vaccination centres.
"By 2pm on Monday, February 1, there had been 60 DNAs (did not attend) at the Bay Field Hospital alone.
"Overall (on Monday) 6.5% of people booked in at the Bay did not attend. These appointments had not been cancelled with the booking centre.
"Faced with mounting spare vaccines which had to be used yesterday or thrown away, our staff volunteered to stay late to use up the vaccine on people called in at very short notice from our reserve list."
Last week it was reported that half of the people in the top four priority groups had received their first jab in Swansea Bay.
The health board urged people to contact the booking centre, by calling the number listed on appointment letters, if you can't make the appointment or do not want the vaccine.
While the health board does "run a reserve list", people can't join it as the booking centre will contact those who are next in line for the vaccine and are in the correct priority groups if slots open up at short notice.
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This comes after some people received their vaccination "ahead of programme" after the booking number for frontline healthcare staff was shared on social media.
Last week, Cardiff and Vale University Health Board explained that the booking number for frontline staff to make appointments at its mass vaccination centre had been shared on social media and apps.
This resulted in some people managing to arrange appointments to have their vaccine "ahead of programme", making it "increasingly difficult" for healthcare staff to get appointments due to the high number of calls being made.
