Why all scripts only works really well on Roblox studio TestMode?

Alright i have been experiencing a lot of my scripts and local scripts work really well on Roblox studio when i test Server it, The only really works on the real server is only Normal scripts and all of my hard work on all local scripts won't even run? how so? but the old days i'm actually really fine all scripts and Local scripts are running fine? wth? is this a new bug for roblox studio? or it's just me? i actually tried making a new game again and copied all the scripts and paste it there and still the same

so i can't even develop my dream game that i'm working on so hard!

it's a bummer and lose all of my inspirations because of these stupid local scripts that can't even run in the real server!!!