If you keep cancelling orders you will receive damaging defects on your account.

Personally,  I would have just ignored those low offers,  or better still set them for the lowest offer you were happy to receive,  that would have made it impossible for the buyer to offer lower.

Maybe they desperately wanted the item seeing their offers were not being accepted bought it for the price listed,  no real need to cancel there.

What was the item what was the price ?

@beesandhoneylondon