Hi Jeremiah,
Visio Plan 1 does not include the Visio desktop app, so did you log into Visio Online?
When you face the same issue when logging into Visio for Web, please go to My Account with your email address to check whether you have the license for Visio Plan1.
Besides, where did you purchase this product? Such as from official Microsoft site, it's best contact Microsoft via chat or by phone.
As we are mainly responsible for general issues of Office desktop applications, any issues related to account and subscription, you'd better find the corresponding support of the store for help. Thanks for your understanding.
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