Some Post Offices can check your passport application - called ‘Check and Send’. It’s less likely that your application will be rejected if you use Check and Send.
Look up a Post Office that offers the Check and Send service. From the drop down list, choose:
‘Passport Check and Send - digital’ if you want Post Office staff to take your photo and help you fill out your application online
‘Passport Check and Send - paper’ if you’re applying with a paper form