Question about stock with batch

I create an item with batch
but the stock is always zero though I have already set opening stock in template
I try to maintain it in stock reconcile section , then the message came out
what does that mean ??


then I went to stock entry to do material receipt
the message came out
plz help me , its really annoying QQ

Are you creating a post-dated Material Receipt entry? If yes, then perhaps in the process of reposting, system is not able to locate valuation rate for one fo the existing entry for this batch item. Hence, please update Valutaion Rate in the Item master of this batch item and try again.