First of all, confirm if the option to delete circulation history is enabled on the OPAC.
When a patron logs into their account onto the OPAC they are automatically brought into an account summary which, depending on the functionalities enabled for them, should look something like this:
On the left hand side there will be a list of tabs for the different functions open to the patron. A system that does not have the OPACPrivacy system preference enabled will be missing a tab in this list called your privacy.
If this tab is missing, log into the staff side of Koha and go to Koha Administration > Global system preferences and search for OPACPrivacy.
Chose to Allow patrons to choose their own privacy settings for their reading history and hit Save all OPAC preferences.
Now, on the OPAC, there is the option for people to delete their reading history in the form of a new tab called your privacy.
In the patron record on the OPAC, there will be a tab on the left hand side called your reading history. This will contain a list of all items the patron has checked out. This is the information that the your privacy tab gives the option to delete.
Under the your privacy tab, patrons can choose what rules to follow in terms how of often their circulation history is deleted.
If someone hits Immediate deletion it will clear their reading history of everything but items that are still checked out, regardless of which rule from above was saved.
In order to delete the item, check it back in and run the Immediate deletion function again.
Look up any items on the staff side that were deleted from the reading history of the on the OPAC.
In the Checkout history tab, the circulation data is still recorded, but it is associated with the Anon patron. See below:
This will be the case for any circulation information deleted from any patron account in this way.