If you have deleted a Plan in Recurly, but still have active subscriptions under that Plan, then you'll notice that these records (invoices & transactions) are not being synced over to QBO.
Unfortunately, recreating that Plan under the same plan_code and plan_name will not resolve the issue, as it won’t change the underlying subscription or the invoice already generated. We keep deleted plans around to link them to existing subscriptions and invoices.
What you can do is change the plan on the subscription to the newly created plan and the next renewal invoice would reference the new plan. However, keep in mind that previously generated invoices will always reference the old plan’s base_fee/setup_fee.