Help with my Website who is Suspended

Hi we received this email about the reason of our website suspension: Please help me fix the website. Our monitoring system has detected email spam on ORLANDO01 from one of your clients' accounts [archetypejoinery]. This account is owned by the sub-reseller [lunar]. It is most likely related to an outdated plugin/script or WordPress version that your client is using, however as with most WordPress malware, the malware usually propagates to other parts of the cPanel account so you will need to ask your client to patch every single WordPress installation. The patching effort should involve the following: 1. Replacing all WordPress core files 2. Looking through all plugins/themes and removing any that is no longer in use (by removing, we mean to delete completely and not just to deactivate) 3. For any plugin/theme that remain in use, your client must update them to the latest version. Take note that it is best the plugin and theme that remain in use is fully deleted first and then reinstalled. Furthermore, take note that if any plugin or theme is downloaded from a third party website, your client should check the website for the latest version. Currently due to the huge amount of spam, we've had no choice but to suspend the [archetypejoinery] account first. Once your client is ready to work on the issue, please let us know his IP Address (he can use something like [login to view URL] to obtain it) so we can provide him with temporary access to work on the issue. Please take note that as per our updated suspension policy, if we do not receive a follow up within the next 30 days, to ensure compliance with the Terms and Services of not just our hosting company but also the partners that we work with, the [archetypejoinery] account will be terminated and a full backup of the account will be offered to you.