To remove disavow from your links, you need to:
Filter your disavowed links by clicking "New Filter":

Then selecting Disavowed >is>Disavowed:

Select the link you want to undisavow, click on the "Disavow" button, and then on "Remove from disavowed list":

Filter your disavowed links by clicking "New Filter":

Then selecting Disavowed >is>Disavowed:

Select the link you want to undisavow, click on the "Disavow" button, and then on "Remove from disavowed list":

Updated on: 19 / 08 / 2019