SDL_Net player synchronization? issues

Hi, I’m developing an Isometric 2D online RPG with the SDL_Net library.
First I’d like to say that there is an authoritative server connecting all the clients, and making sure that there is no hacking going on etc.
I’ve things like registration, login, and some player synchronization done.

But I have a problem with the player synchronization I think?
When a player moves his character, turns just after moving, then stops moving - other connected players will see that character keep moving whilst the player who moved will see him/herself stopped. On the server, the player is on the coordinates on which the player stopped, but other clients simply see the player still moving, ignoring any and all obstacles in his/hers way.

Here’s a video to show the problem going on:

I’d love to show code, but I can’t show the entire code. If you need some code samples, please let me know - however I think theory on why this is happening will aid me.

I hope someone can help me clear up this problem.
Thanks in advance.

relevant client side code https://pastebin.com/wyVfj7hk

Relevant server side code

https://pastebin.com/yBXNbsfU

When I’ve written network games I’ve always had all of the game engine running on the server, and the server just informs the clients of what to display, so everything is always in sync on both.

The engine is running on the server, and the server already just informs client what to display.
Client can’t really do anything on it’s own.

Can you provide a print out of the messages been sent to clients ?