I appreciate you for letting us know here today, titanuplawncaret. Let me provide insights to help rectify missing option when sharing invoice links with your customers.

Based on your screenshot provided, you're using the QuickBooks Mobile app. The stored cache may cause unusual behavior in the program. We can perform some troubleshooting steps to refresh data into its default state. This process plays the same role as clearing the cache from your regular web browser. To do this:

If you're using an iOS, follow the steps below:

1. Go to Menu ☰ and tap Help & Feedback.
2. Tap Refresh Data.
3. Click Refresh to confirm.

Otherwise, refer to this instruction for Android:

1. Go to Menu ☰, then select More Options ⋮.
2. Tap Settings, and click Refresh Data.
3. Tap YES to confirm.

 Also, you can perform some fixes on any app-related issues to rectify stored cache data on your mobile app. Here's how:

1. Change the Wi-Fi data connection on your device to 4G (this varies by device).
2. Close and restart the app.
3. Clear app data. To do this:
4. Open your device Settings.
5. Select Apps.
6. Choose the QuickBooks app from the list, then select Storage.
7. Select clear data.
8. Power down and restart your device.

If the issue persists, uninstall and reinstall the mobile app. It's to ensure you get the most recent version of the application. To do so, refer to this page: QuickBooks Mobile App. 

Moreover, I'm sharing this reference to help you track and record customer-paid invoices in your account: Receive an invoice payment using the QuickBooks Online mobile app.

I'm always ready to back you up if you require additional assistance managing customer-related tasks. Feel free to reply below, and I'll ensure to get you covered at any time. Have a good one!