i cant execute a trade in demo account. and i have attached the screen shot.
Thanks for the question and welcome to the community forum!
I believe I see the problem, it appears that you may be attempting to place an order for a continuous contract. This is represented by an @ symbol in front of the contract you are trying to trade. Although analyzing data with a continuous contract is fine on a chart, MT5 does not allow users to trade off of these symbols.
Instead, I encourage you to add the Dec '19 CLE contract on your Market Watch board and then attempt to place an order for it! Just right click on the CLEZ19 contract once you have added it and check whether or not the New Order option is available. You will immediately know whether or not this was the cause of the issue, if you can place an order for a specific contract month, then the continuous contract was the issue.
If you still cannot place an order for a specific contract, I am under the assumption that your demo is expired!
Let me know if this solution works for you, I am curious to see whether or not the continuous contract was the underlying issue.
Thanks for the question and I hope you found this helpful,
Optimus Futures Support