/shop-2/ /shop/

/shop-2/ /shop/

I have been seeing this strange alteration to my url which is baffling me and causing one of my menus to disappear.

if i see (shop-2) in the url my main menu vanishes
but if i see shop then it is there has anyone else had this issue and is there a fix

links so you can see
http://www.peterboroughmedical.co.uk/shop/accessories
http://www.peterboroughmedical.co.uk/shop-2/accessories

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