This is a major issue with your phone and on the forum for your phone, many people are complaining about this. They have so many requests to the manufacturer to upgrade and fix the software, but they aren't responding to this problem. Apparently, on this phone, there are a few other bugs that have not been addressed and people are angry with the company.
You are correct this option on your phone has been blocked and people are requesting a software update to un-block this option. You will need to wait until the company updates the software in order to hide your caller ID. For now, there is nothing that you can do. I'm sorry.