I have found some items in the P&L under "purchases" despite them having specified accounts. It isn't one specific item there are various different ones.

Hi accounts-control, thanks for posting on the Community

Do the transactions posted under purchases relate to transactions that were migrated from QuickBooks Desktop?

Purchase orders are non-posting transactions in QuickBooks Online; it is only the converted bill that posts to accounts. You can view the specific accounts that a bill or bill payment is posting to by selecting More > Transaction journal on the toolbar of the transaction. 

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