Why won't an insurance company tell me the amount of a life insurance policy even though I'm the beneficiary?

So my brother ped away a couple weeks ago and left everything to me. He had 5 life insurance policies through prudential and I was the beneficiary on all 5. The day that I talked to the rep, he told me the amount of 4 of the 5 but said he could not tell me the amount of the other. They sent me the claim form which had all 5 policies listed on it, for me to sign. I sent it back and I received checks for the 4 they told me the first day, but still not the 5th. Anybody know why they won't tell me the amount or why I haven't received the last check yet?