Sam trade were announced as 'partners' last autumn. At the time they said the name was to appear on the back of the shirts. Are 888 a subsidiary of SamTrade? Maybe that was part of the deal.
Sam Trade are the sponsors on the backs of the match shirts (above the squad name). They are a currency trading company.
888 are the sponsors of the training kit. They are a betting company and nothing to do with Same Trade.