Hi,
I hope you're doing well. We apologize for the delayed response and trouble.
As correctly pointed out by the Engineer, if you're using Acrobat 11, which is an End of Life product, you may encounter issues. For more information about product support, please refer to this article: End of Support for Acrobat XI and Reader XI.
You can download and install the latest version of Acrobat and activate it by signing in with the Adobe ID (email) associated with your subscription: Download and Install Acrobat Subscription.
I hope this information is helpful.
Thanks,
Anand Sri