Join server my friends

Hello, I still have trouble joining my brother in his world for over 3 months.
Every time we try to connect to each other (ps4 + ps4) it is not possible to time out and it is not possible to connect to the world. Error ejection window.
We tried everything, you just can't play the common world.
Where can there be a mistake?
Please advise thanks to JezisekGamerCZ and JonyPlayerCZ