Im having this issue and really need help asap

So i try loading up my server, everything is alright, server and client are on the same modpack version but when i try to join my server the Incomplete set of tags error comes up, i really need help. I was looking everywhere for help even on discord but it didn't help at all.

So, server logs don't show anything spectacular just me joining and leaving with the message "disconnected" after a second, but client logs i think show the problem but i don't reall know what they are saying.

https://pastebin.com/bUtti0Aj

Please help, thanks!