Edit PDF online doesn't work now though having a premium account (recently the function worked)

Hi Julia,

Thank you for reaching out.

Acrobat premium subscription is for the mobile application.

It will not work on the Acrobat Online account. You might have used the one free trial of the feature for the Acrobat online account. 

You will need an Acrobat Pro DC subscription to edit PDF on your Acrobat Online account. For more information, please refer to the following help document:

Acrobat Pro DC subscription: https://helpx.adobe.com/acrobat/faq.html.

Let us know if you have any questions.

Thanks,

Meenakshi