profit and loss by class is only showing income not expenes.please reset the company configuration

The Profit & Loss report should display expenses if there are any expense transactions within the chosen period of the report, @Maria-Nasimiyu.

When you run the report, ensure that you check the Report period. You can choose Custom dates or any period you want to check. Also review the filters applied. Ensure that the Account type is not filtered to Income accounts.

Please see the sample screenshot below on how to choose the Report period and Filters.

For the Account type filter, choose All Income/expense Accounts.

The Profit and Loss report should now show the Expense accounts.

Don't hesitate to comment below if you have questions about running reports in QuickBooks Online.