Edit existing members error

I have a number of members subscribed to my website, with two different membership levels. If I go to the list view, I can click on any member and edit their account. However, when I search for a specific user and then click Edit on the results, I get directed to a page that says “You do not have sufficient permissions to access this page.”

I have full admin access on this website and am able to access and edit all areas of the site. to reiterate, I can edit Simple Membership user accounts if I search for them manually by clicking through each page of members, but when I use the search function to find a particular member, I receive the above message.

Please help.