Alisa, I cannot explain why the units are not available for removal. All the lengthy delays you’ve experienced with the previous removal orders and the fact that you cannot create new removal orders implies to me that perhaps there is some issue with your inventory that Amazon needs to investigate. As Amanda suggested, contact Seller support and ask for this situation to be investigated and then resolved. Make it clear to them that the removal orders were submitted months ago and now you cannot request any more removals. If you don’t get a satisfactory answer the first time, then just keep submitting cases until you get someone who is capable of helping you.