According to the Sunday Telegraph, Welby was marrying his head of media relations Ailsa Anderson and veteran journalist Simon Cole on 16th September.
In the middle of the ceremony at Lambeth Palace the Archbishop said he had only been given one ring.
However, both rings were place on top of the order of service which the groom's son gave to Welby. The son deduced that the bride's ring must have fallen out of Welby's hand.
It's official! I am now Mrs Anderson-Cole ❤️ pic.twitter.com/d6sXchtZYb
— Ailsa Anderson (@AilsaJAnderson) September 19, 2017
The paper said the wedding party frantically searched for the ring and found it under a nearby chair after a moment.
The bride told Sunday Telegraph that at first the Archbishop thought it was the groom's son's fault, but then admitted it was his mistake.
She added that he delivered a "lovely warm speech" at the reception and has been "so kind" to them.
The ceremony is the first wedding the Archbishop has officiated since he married his daughter Katharine to Christian songwriter Michael Roberts in 2014.
