RE: In cash journal, I can't post the payment, is there any one can solve this issue for me?
While this row in the screenshot is highlighted, click Lines in the ribbon. This will show the details (Starting No., Ending No., Last Used No., Warning No., etc.). If the Last Used No. is not close to or equal to the Ending No., don't bother messing with the Ending No. value.
From your screenshot, it looks like "Manual Nos." is now checked for the Cash Receipt Journal no. series (GNL-RCPT). When you go back to the Cash Receipt Journals list, verify that your batch has the same No. Series assigned to it. Now, go back and edit the batch and try posting again with the manually entered Document No. and it should let you post it. If that doesn't do it, you may need to debug to see what's causing the issue.
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