There are a few reasons why it might not be possible to delete your OkCupid account. First, OkCupid may have cookies set up on your device that keeps track of your activity on the site. If you delete your account, OkCupid may be unable to access those cookies and may not be able to delete them for you.
There is no one-size-fits-all answer to this question, as the best way to disconnect your Instagram from OkCupid may vary depending on your account and settings. However, some tips on how to do this include finding a settings guide or setting up a blocking rule in your OkCupid account.