Безопасен ли jumia.com.ng?

I have problem right now with them and I am really pissed up as I ordered goods to be delivered for my mother in law whilst I live in england.I feel like to call police to investigate the matter because every customer service advicer said diferent thing.They basicaly canceled my order after received payment from me saying they will send the voucher which I can use to order diferent thing on their webside of which they did but it was not possible to proceed checkout WITH the voucher .... only if I pay.So second time I choose pay on delivery and send voucher number to my mum by text so she can show the delivery man and send the message on 3 different emails about it .... yet nobody replied so far.Another thing is day after cancelation my husband called and asked them about the item we actually ordered if they have it in stock and they said yes which makes me feel they just trying to rip me of when they found that I pay from abroad.I am not rich person ... I have to tighten really hard my budget if I am to buy something like I did now for £90.I just feel like to cry .... It was supposed to be gift for my mum ,new mattress as hers is not possible to sleep on any more and my husband is very very angry.