I am new to QBO and am frustrated that I cannot import my memorized reports from desktop. I need a report that includes all invoices and payments for a specific period.

I understand the frustration, @MLovelace.

Unfortunately, Memorized Reports from QB Desktop will not convert to QBO. You will need to recreate the reports in QuickBooks Online and memorize them again.

To get the report you'll need, you can run the Invoice and Received Payments then select the specific period from the drop-down arrow. This will give you the list of payments from a certain period and the invoices that the transactions were applied to

Here's how:

1. Go to the Reports tab.
2. In Type Invoices and Received Payments in the search field. Or scroll down then go to the Who owes you column.
3. Select a date in the Report period field. 
4. Click the Customize to filter the report.
5. Hit Run report.

You can also open the  Transaction List by Customer report and filter the Transaction Type to Invoice and Payment.

For complete guidelines in sorting and customizing your reports, check out this article: How to Customize Reports: Basics, Sorting & Date Ranges.

In case you want to memorize the report, just click the Save customization at the top-right corner. Then, you'll see it under Custom reports. For more details, click this article: Memorize reports in QuickBooks Online.

Also, I'm adding this article to know what other data don't convert when you migrate from QuickBooks Desktop to QuickBooks Online:  What to expect when you switch from QuickBooks Desktop to QuickBooks Online.

Please know that I and the Community are available to help if there's anything else you need. Take good care!

Thank you!