Missing items on delivered Order #***

I placed an online order for my kids school stationery early this month. When I received theee the order, It was short by 2 packs of 3 pritt glue 22g. I sent a query email and their response was I received the order. Yes I received the other items I ordered except for the 2 packs of pritt. This is really frustrating, I used my last cash and its the middle of the month. In the meantime my kids are going to school without glue. I'm so angry, frustrated, disappointed, stressed and my kids and I are suffering as a result. What is more hurtful is that, I have to spend what I don't have to go buy something that I paid for and never received.