I accedentally deleted a Online saved score and i really need it, its called Драгоево хоро, i would be greatfull if you could help me find a way to retrieve it!

You get a warning before deleting an online score:

So you need to look on your own computer for any backup files. Try reading these posts:
- Recovering autosave/backup files in MS4: https://musescore.org/en/node/352110
- Does musescore 4 save backup files? https://musescore.org/en/node/341775
- Musecore 4 Autosave Location: https://musescore.org/en/node/351724