If the items in question were purchased over sixty days ago then they would automatically disappear from your Purchase History, although you can see them again by clicking on the drop-down icon and clicking where it says "2020" in order to view everything that you've purchased this year. You can also bring up everything you purchased during 2019 and 2018 by clicking on the relevant year in the drop-down menu, although the page always defaults back to the option to show you purchases made during the last sixty days.
In the event that you've purchased items within the last sixty days and you cannot see them in your Purchase History then it may be worth contacting eBay Customer Service about the matter to see if there is anything that they can do from their end to rectify the problem. If you click on the Help & Contact link that appears at both the top and the bottom of this page then when the next page loads up scroll right down to the bottom of the page and click on the mobile phone icon beneath the words "Need more help? Have us call you" and you should receive a phone call from eBay shortly afterwards so that you can discuss the matter with them.
