Globe Life Insurance No pay out for my grandson Internet

Hello

I took out a life insurance policy on my children and grand children. I have had theses policies for years and have made my payment the same every month. I would send in a money order with all of the policy numbers written on them. I have never missed a payment. I have all of my reciepts. My grandson died on March 11, 2015 and I called the insurance company and filed the claim and now on the 23rd of March I received a letter stating that my grandsons life insurance had lapsed in February, even though I sent the payment in on March 3. I called them back and they said that my payment had been applied to only one of the policies. I do not understand why they did not apply the payments as they had int he past and now we have had the funeral with the undestanding that the insurance would cover the cost. I have called them and tried to sort this out but I keep getting the same story. I feel as though I am going to lose out because they made a mistake and won't own up to it.