Abacus24-7.com Tracking Order Status

I bought a case for Samsung Galaxy S7 from them. I bought that thing for a business entity, so for reclaiming the money from the business I have to provide the invoice. But they sent me wrong invoice - not a big deal, errors happen. However contacting them was very hard. All emails are responded after 2-3 days, and each time they send me another incorrect invoice. Customer service is non-existent in this company - so I'd say: avoid them ! Update: they finally made it. And I would say 3/5, but instead of making everything cool&happy, they tried to tell TrustPilot, that my comment is invalid, because I never bought anything from them. Obviously a lie, and I have proven this with the invoice. One more bad point to how this company acts with customers. However 2/5, because at least the product itself is quite good.