Downloaded map wont load

So, about a month or so ago, I started a modded server and spent a good amount of time on it and built a few things, I decided iI should save a backup of it on my computer, for general backup stuff and also in case i wanted to try something in creative outside the server, so I downloaded the map, but once the map was finished downloading, I tried to open it and it wont load past the chunk i was standing in, also nothing would update no blocks that i broke would drop no block would be placed nothing, it looked like i was in a server that was about to rollback, but i was in single player.
Any ideas as to why this is happening or if there's anything i can do to fix this ?

Okay so i decided to try it again today, i have tried this multiple times before and i dont know why it just worked i did turn off Optimize b4 trying it again maybe thats what did it ? im not sure regardless iguess it works now if anyone has this issue too try turning off Optimize and download it again idk

(edit: i was too quick to selebrate it stil ldoesnt work its just taht more than one chunk loaded this time and at first glance it was fine but its not fine, some little more of it loaded but then it straight up crashed also mobs couldnt spawn)