It looks like your account was suspended 4-years ago, and you were notified about it through this support ticket. You should be able to access the same ticket thread by going to the email inbox associated with your Upwork account and looking for the email with the subject "Action Required. Temporary account suspension." Kindly refer to the ticket thread for more information about your account, and how you can lift the limitation to your account.
Let us know if you need anything else, and our team will assist you further.