How can I request a refund for accidental subscription charge for Meta?

My daughter was in instagram and subscribed mistakenly for meta and she would not mean to purchase. 2 days later my husband found the money withdrawn from his account, cancelled the subscription and requested for refund 2 times but refused. They got £274.99 from his account, however he has not used it at all. It affected financial balance for this month and made very bad experience with apple. The thing we have not experienced with google pay before at all. How can we appeal for that??

[Re-Titled by Moderator]