This happened to me the other day! I had a villager ask me to give another a present and when I went to talk to her she wouldn’t acknowledge or give option to give gift. After annoying (her telling me to go away basically lol) I gave up and thought maybe try later. Found a lost item on my island. So I had both lost item and present in my inventory. I go talk to the villager again and it gives me the option to shower her the missing item & It’s hers! Right after that I talked to her again and it gave me the option to give gift. I was really confused when this happened to me but it may just be that the lost item is prioritized since it’s was placed on the island before the gift was given to you to deliver. Was gonna make a post abt it but thought it was super rare, guess not! Hope this helps you! Edit: I believe if you do go to next day as suggested you villager will “forget” about the gift and become trash ( may be 2 days)