Most certainly you're experiencing the tactics of the British Cartel...
a notorious group that plays this ongoing game until they get the price
they ideally want to get for an item... they literally buy it from
themselves if the pricing is not achieved, and re-list under any one
of (currently) 4 or 5 different
ebay ID's...
There has been quite a bit of discussion about them over time, here
on SCF... a search on the subject will yield you quite a bit of info...