When i try to create a ne invoice some of my products will not populate into the invoice when i select them from the drop down. i have cleared all the cache and cookies?

Welcome to the Community, Jaco.

I'm here to provide information about products and services in QuickBooks Online (QBO). But before anything else, I appreciate you performing some troubleshooting steps to isolate the issue. 

The products and services that populate in the dropdown are active items. There's a possibility that you may have accidentally inactivated some of your products in QBO, which results in some of your items not showing in the Products/Services dropdown when creating an invoice.

To make sure that the products you want to select are active, here's how:
 

1. On your QBO account, go to the Gear icon, then select Products and Services.
2. Click the Funnel icon.
3. From the Status ▼ dropdown menu, select All, then click on Apply.
4. Find the product or service that you want to populate in the invoice.
5. To know the status of the product or service, refer to the Action column.
   
   

If the products were made inactive, you can click on Make active to reactivate them.

For detailed information, kindly visit: Remove or merge a product or service.

On the other hand, if the products were active but still won't populate in the invoice, it could be something to do with browser issues. 

QBO can occasionally stop working properly since locally stored internet cache files can cause the product to behave unexpectedly due to overloaded site data. I recommend opening a different browser or a private window to isolate possible issues. This can help us remove any cache-related matters that may have contributed to the problems.

Here's how to activate incognito mode in some of the most common online browsers:
 

• Google Chrome: Ctrl + Shift +N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P
• Safari: Command + Option + P

If you're finally able to see the products/services in the invoice, it's safe to say that the browser has caused it. This can be fixed by clearing your cache and cookies.

Moreover, I'll also share this link where you can search for articles that can serve as your reference to guide you to add, organise, and send invoices in QBO: Invoices and Payments Help Articles in QuickBooks Online.

I'm looking forward to hearing back from you. Feel free to leave a reply if you require further assistance with populating products and services in the invoice in QuickBooks. The Community team always has your back. Have a good one.