If you have two accounts, you really can not "delete one and keep the other" on your own.
You really need to work with Upwork Customer Support to handle this properly.
If you are caught with two accounts, you could have all of your accounts suspended. But if you are proactive and go to Upwork and ask for help to close the extra account(s), they will work with you and you won't be in trouble.
This thread has been flagged to get a moderator's attention. You could just wait for 24 hours before trying anything else. Somebody should be by to help you with this.
I checked the link you shared, and it looks the account is active. You may log into your account to check. I would also like to remind you to please avoid creating a duplicate account as it is a violation of Upwork ToS. You may now close this account that you used to post here in the community. Thank you.
Thanks for the reply. Last I tried loging into that account it said account doesn't exists. I'll close my current account and log-into the old account now.