ERROR: Only Admins Can Place Trades- what does this mean?

This means that the Evaluation account has been failed and has been disabled. 

It either means you have reached your Trailing Threshold Drawdown or that you have held a trade past 4:59 PM ET.  For more information on both of these please see below. The Help Desk does not have any other information other then what is shown here.  In these videos will walk you through how to see and understand exactly what happened.  You can also see all this right on your own computer and monitor it ongoing:

Trailing Threshold: https://apextraderfunding.zendesk.com/hc/en-us/articles/4408075679643-How-does-the-trailing-threshold-work-  

There are really only 4 rules to follow with the Evaluation Accounts, and these are two of those rules:

https://apextraderfunding.zendesk.com/hc/en-us/articles/4406411098779-What-are-the-rules-for-evaluations-

You can reset your account and start over with full balance and trailing threshold: https://apextraderfunding.zendesk.com/hc/en-us/articles/4408072878619-How-do-I-reset-my-account-