It appears you bought this set on the 19th & downloaded it on the 20th.
BiMgirls uses cookies to remember who bought a set so there is no need to register or remember passwords. However, the cookies do expire in order to prevent illegal download sharing.
I've extended your download and you should be able to download again today only.
In future, please use the support email at the bottom of every page if you have a question otherwise we end up clogging the main timeline with tech support messages.
Thank you!