how to block the premium

Premium Membership to what exactly?

If it was purchased from Google Play or Apple Store, you may need to contact them.

If purchased directly from Adobe, see below.

Log-in to your online account.  Click on Manage Plans > Cancel.

https://account.adobe.com/plans

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How do I Cancel my Subscription?
https://helpx.adobe.com/manage-account/using/cancel-subscription.html
===============
Subscription & Cancellation Terms:
https://www.adobe.com/legal/subscription-terms.html

CONTACT ADOBE SUPPORT:
================
Online Chat: https://helpx.adobe.com/contact.html?rghtup=autoOpen
Phone M-F, during normal business hours: https://helpx.adobe.com/contact/phone.html

Hope that helps.

To Cancel https://helpx.adobe.com/manage-account/using/cancel-subscription.html
-or have Adobe support cancel your subscription using the "autoOpen" Chat link below

Be sure to remain signed in with your Adobe ID before accessing the link below
Do be aware that Adobe's staffing is impacted by the Covid virus, so wait times are long
.
You MUST make sure that your browser does NOT block ads, scripts, or pop-ups
You MUST also allow 'cookies' in your web browser for the link to work
.
This link will go directly to the chat option
Type "Agent" in the chat box to bypass the chatbot and be connected to a person
-Meaning type in the word Agent without the quote " " marks
https://helpx.adobe.com/contact.html?rghtup=autoOpen
- or by telephone https://helpx.adobe.com/contact/phone.html
- or Twitter tweet @AdobeCare
.
Adobe does NOT do support by email, so beware of answering anyone who sends you a private message
-click for more information about scammers https://tinyurl.com/10791730

or do you mean you have adobe premiere for desktop?

@Alessandra28045289nfqr 

You posted to Using the Community (for questions about the forums). It almost sounds like you purchased the Premium version of Adobe Acrobat Reader for Mobile?

Please confirm. Also, are you on Android or iOS?

Jane