EntityFramework.Core.Tools nuget package installation error: "The process cannot access the file ef.exe because it is being used by another process"

While installing the package Microsoft.EntityFrameworkCore.Tools for using EF in my project using Nuget, I'm persistently running into the below error. Notice I didn't get any error while installing other related packages used for EF core

• Microsoft.EntityFrameworkCore
• Microsoft.EntityFrameworkCore.Relational
• Microsoft.EntityFrameworkCore.SqlServer

Here is the location of the file ef.exe

Basically the intention behind installing this package is to use EF command-line tools. I'm currently on Windows 10 and the .NET SDK installed on my machine is 3.1. I had previously 2 SDK's installed on my system(3.1 & 5.0). As per microsoft's documentaion, "The .NET CLI must choose an SDK version for every dotnet command. It uses the latest SDK installed on the machine by default." Therefore I went ahead and uninstalled .NET 5.0 SDK

Here are some of the solutions that I tried:

1. Deleting the package folder from '.nuget/packages/microsoft.entityframeworkcore.tools'& thereby the executable i.e. 'ef.exe' and reinstalling the same.
2. Installing the same package using dotnet cli.
3. Running Visual Studio 2019 as admin.
4. Deleted the folder "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions"

I have also tried some of the steps mentioned here on github: https://github.com/NuGet/Home/issues/1138. Any kind of help would be really appreciated.