update failed, would like to try installing manually but can’t download package

I decided to pay my MailPoet 2 installation, but when I tried I got an error. I made sure I had enough room in hosting account (I did) and tried again, and this time the error said that the directory still existed. So I went to buy FTP, deleted the directory, and tried again. It still gave me an error, so I decided to switch back to trusty MailPoet 2 for the time being. It won’t let me install or download the old version because it thinks I still have it installed. Any ideas what I can do to get things working again?

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