As stated by the title, me and my friend were playing in our server, and I was the only OP. Suddenly, my friend couldn't open chests and barrels, interact with anvils and crafting table. I've reset the server, he reset his game, and it's still the same thing. I tried giving server operator role, and then he was able to interact with all of the stuff mentioned. I tried it, deOP'ed myself and also couldn't interact with the things. Does anyone have an explanation about this or a fix? I would appreciate some help, thank you!