I noticed this happening a lot more often since the Enchanted by nature patch:
I was playing with a fairy, trying to do daily activities like getting to know other fairies in the lounge, asking them for fairy dust, and it cancelled out so many times after pushing it into the queue. It appeared to me like some other Sim was targeting mine for something and that cancelled all my interactions. I noticed similar things happening on my own lot, when trying to garden or do other activities outside, and suddenly some other sim came from far away to mine, and for the whole time mine was just standing still not doing anything until that other sim arrived and did their action. This cancelled my own Sim's interactions out though.
