For experience,
Starting with a question, did you add a module, new module ?
Or have you some modules in game ? If yes:
This modules are something like crafting, or gamestore , or things that you can add "more and more" things on it, like items to sell, outfits, crafting recipes, etc ?
It can probably have a limit, just try disable one by one module to see the module doing that, after if it has something on server, delete some lines example if is a gamestore, delete and just leave 10 lines for example and try, check console in game, if is clean then you will know that there is a limit and you need to fetch a limit of sending this information to the client.
I lose many weeks looking for something similar without understanding where it comes this type of error, "check logs", yeah numbers and leters but for a newbie... good luck to understand from where it comes.
After just disabling all modules and start one by one i see that a gamestore posted here, if it has many offers, it starts sending errors about others things: nothing on position stack pos x y z, cannot create item 42390... ( id non existing ) and plenty of this.
Try and let us know if is that.