In your first link, that PQuote was already closed/converted to a PO, [cetec url]/purchaseorder/1236/view
Subsequently, it looks like that PO is also closed, because the linked lines from the sales order are closed. If you need to, you should be able to clone the PQuote and generate a new PO that way.
Same thing with the PO from your second link, that PO is closed because the linked sales order line was closed. If you need to, navigate back to the PQuote on the left side of the PO, clone the PQuote, and process a new PO.
Hope that clears this up a bit for you, let us know if you have additional questions about it.