For Online Banking you can view your credit card statements for the past 4 years. In the mobile app you can view your statements from the previous 2 years.
In order to view your statements online, under the section 'Your statements', select 'Statements' and choose the relevant credit card if you have more than one.
Within the mobile app click on your credit card account then 'My Statements' and choose the year of the statement you want to view.