Upgrading from 2GB to 6GB, and then to Unlimited (Payment)
I had purchased the 2GB storage and soon (on the same day) realized that I needed more. So I changed the plan to the 6GB plan, then to Unlimited. I have a receipt for the 2GB storage, but not for the changes ones. How and when are you going to charge me for the changed plan?
https://www.zotero.org/support/storage_faq#how_can_i_upgrade_to_a_larger_storage_plan
You can see the receipt for the transaction at https://www.zotero.org/settings/storage/invoice