Bubbelgum tablets

Hi, My kids saved up to buy them selfs each a Bubbelgum tablet. It took only one moth for my girls tablet not to work and both the earphones were not working. I took it back to Musica Langeberg Mall. We had great service from Musica but the product is truly of bad quality. After it was send back we received the tablet and it worked till we needed to charge it. It's not charging. Once again I need to take it back? This is unacceptable from something my kids spend their hard earned money on.