Downloading mongoDB error

Last month downloaded mongoDB onto my Ubuntu 20.04 using sudo apt install mongodb-org I found the package, installed it and mongodb was working fine. I however deleted it and when I try reinstalling it the same command outputs "Cannot locate file mongodb-org". sudo apt install mongodb работает, но sudo systemctl start mongod.service выдает «Не удалось запустить mongod.service: Unit mongod.service not found». Как мне это решить? I once set my ubuntu software to download from Main server, but it was originally downloading from my local home country server, which I changed the setting back to. Could this be an issue?