Custom booking length issues

[Julie462]

I have a 3 night minimum booking setting and never set a custom length for less days at any time. Twice recently guests have been able to book trips for less days e.g a one and a two night trip. Each time this happened, I have checked my custom length and weirdly those particular dates and length of trip appear there retrospectively as available. I did not set them. I have contacted Airbnb, who offered me the chance to cancel without penalty and said they would look into it. Has anyone else had the same experience?