I want you to note that the read-only error message often indicates that you're using an expired QuickBooks Online subscription, @yolonation. Let's go through the specifics of your QBO subscription to address the problem and ensure you can create invoices without any further interruptions.
When you renew your expired QBO account, it will automatically reactivate, allowing you to create sales forms like invoices. I appreciate your efforts in troubleshooting through your browser, however, since you mentioned you're unable to subscribe due to already being subscribed, I recommend reaching out to our support team. They have the expertise and tools to investigate your account and assist in reactivating it.
To reach out to our QuickBooks Support Team, visit this article for the support number or go directly to this website: Contact QuickBooks Support.
Once reactivated, you can check this article to help you manage your QBO-subscription moving forward: Manage billing, payment, and subscription info in QuickBooks Online
On the other hand, you may also personalize your invoice to make it more fit with your business looking.
For future concerns, remember to make this thread active by entering any additional questions you may have regarding your QBO-subscription or in creating an invoice. I'm always here and ready to help whenever you need.