I'm the realm owner and can't use commands like tp

I have recently created a realm for me and my buddy to play on, this was about two months ago. When we first started I was able to use commands easy with no problems but found out he wasn't able to. I found out that I can make him an operator and than did so. We started playing with no problems everything was perfect. After about a week I couldn't use any commands anymore but he still can. I don't know what happened, I didn't mess with the settings after the initial part of me turning my friend into an operator.

What I expected to happen was...:
For Minecraft to work and me not pay 7.99 a month for a broken realm

What actually happened was...:
I pay 7.99 a month for a game that I can't fully use because it won't let me do the simplest of commands

Steps to Reproduce:
1. Create a realm
2. Add a friend
3. Make him an operator

4. Wait till you (the owner) can no longer use commands