Item randomly loses stats

Bought a 1 div pair of boots from PoE trade. Confirmed item was correct in the window. Commenced the trade. Applied jeweller's orb and item goes to normal rarity.

I did not have any scouring in stash for the day and confirmed the item did go from 3 sockets to 4 sockets.

I have never seen this before thankfully.

Item contained normal non-unique modifiers such as #% increased ES and good Res with T1 Int + T1 movementspeed.

First thought was accidently scouring item but the item sockets changed from 3 to 4. Engineering orb only works normal to rare but I went rare to normal.