Why Dua Goes Unanswered?
Read the portion of Sura kahaf where God shows His concern and his intervention with is people even in some minor things to benefit them. at the same time, the damage to the boat for the sailors and murder of the boy for his parents were disastrous, but still it was in their favour. We human being are given very little knowledge we do not know what is best for us, only God knows. if he intervenes at your request or does not intervene, it all is for the good of us. He might want you to struggle with your problem and come out strong.