We appreciate you taking the time to bring this matter to our attention, jannieandmarty.

While checking our system, I found an ongoing investigation (INV-112594) regarding the inability to select the GST code. Rest assured that our product engineers are fully aware of this issue and are working on resolving it.

I also recommend contacting our support team and providing them with the investigation number above so they can search for this in their system and add you to the list of affected users. By doing this, you'll receive an email notification once there's an update on the investigation's status. 

Here's how:

1. In your QBO account, select Help (?).
2. From the Assistant tab, you can enter Talk to a human or Start a chat, then enter your concern. 
3. QB Assistant will provide you with some options which you can use to resolve your concern. You can click No, I want to talk to a human.
4. Click Contact Us. 
5. You may choose to Start a chat or Call us.

In the meantime, we can manually record the transactions according to their corresponding tax code. Kindly follow these steps:

1. Go to the +New icon, then choose the transaction you want to create. 
2. Fill out the required field inside the transaction. 
3. Click the GST dropdown, then select the appropriate tax code for your item.
4. Once done, click Save and Close to exit the transaction or Save and New if you want to create another entry.

To see the availability of our support, you can visit this article: Contacting QuickBooks Support. 

Please let me know if you have further information as you contact our support team. We will be here to provide you with assistance.