I also received an email advising this.
You sent me an email notification regarding payment expiring, however the accounts.adobe.com uses a non standard certificate and no browser will work. account.adobe.com did work however. You may want to review the link being emailed out. 

Hi Kay H,

Thank you for reaching out, and sorry for the trouble caused.

As you wish to change the password for your Acrobat Sign account, it will be done via the steps suggested here: https://helpx.adobe.com/account/individual/sign-in-and-security/security-and-recovery/reset-adobe-password.html. 

Please try clearing cache and cokkies for the browser, beofre trying to change the password. 

Let us know if you need any help.

Thanks,

Meenakshi