I understand that this needs to be looked over, RachelHorizon. We are here to help and will do everything possible to make things right so you can juggle other tasks in your business.

Within QuickBooks Online (QBO), users who initially connected an app have the ability to disconnect it at their discretion. By visiting the Intuit App Center, unlink the connection between the respective programs.

Here's how:

1. Go to the Apps from the left menu.
2. Choose My Apps.
   
3. Find Melio from the list. 
4. Tap Disconnect from the Action drop-down arrow. 
5. Complete the short questionnaire.
6. Click Confirm Disconnect to remove the app from your company profile.
   

However, if you're unable to find Disconnect in the menu, select Settings. Then, click the Disconnect button on the page.

If you're not the user connected to the app, I suggest switching access to it. Since only the Admin can connect and manage apps for the company. I'll guide you on how to do it.

1. Go to Apps from the left menu.
2. Search Melio. 
3. Select Get app now.
   
4. Check the Authorization page and hit Connect.
5. Verify the message details and choose Switch Admin.
6. If necessary, adjust the settings. 
7. Ensure the app is associated with your user ID.

Once done, follow the first batch of steps to disconnect.

For detailed instructions about this process, check out this article: Disconnect An App. 

Furthermore, if you plan to cancel your subscription with Melio, it's recommended to contact their support team. Disconnecting the app will solely eliminate the connection from your QBO account. For their contact details, please follow this link: https://quickbooks.intuit.com/app/apps/appdetails/melio/en-us/.

Let me also share this page that will guide you on how to make a manual bill payment: Enter Bills and Record Bill Payments in QuickBooks Online.

Tag me in your reply if you have more questions. We're just right here to offer our help anytime you need it.