Error with EF when trying to save changes - asp.net

Question

I have an angular 8 app with .net core web api 2.1 and MS SQL SERVER.
I have login and logout implementation for users.
After the user logins, he can add or delete programming langugages.
When I perform a delete operation, I get the error
database operation expected to affect 1 row(s) but actually effected
5 rows
But the code works properly for finding that particular user and the ID of the programming language that he wants to delete.
Here is the image from the table: https://imgur.com/a/taZtJ7d
As you can see there are no duplicates.
I think it is something about Concurrency Conflicts. That's why I added a try-catch block with DbUpdateConcurrencyException.
It works sometimes and sometimes not.
Here, you can find the definiton for the table https://imgur.com/a/YMCYkNy
When I try the following method to delete Users from MS SQL, it works as it should:
public async Task<IActionResult> DeleteProgrammingLanguage(string userId, int plId)
{
UserPL ps = new UserPL();
try
{
ps = await _context.PlUsers.Where(x => x.UserId == userId && x.ProgrammingLanguageId == plId).SingleAsync();
_context.PlUsers.Remove(ps);
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException ex)
{
throw ex;
}
return Ok(ps);
}

Answer 1

I solved my problem with this solution.
public IActionResult DeleteProgrammingLanguage(string userId, int plId)
{
using (_context)
{
// Fetch a person from database and change phone number
var ps = _context.PlUsers.FirstOrDefault(x => x.UserId == userId && x.ProgrammingLanguageId == plId);
// Change the person's name in the database to simulate a concurrency conflict
_context.PlUsers.Remove(ps);
var saved = false;
while (!saved)
{
try
{
// Attempt to save changes to the database
_context.SaveChanges();
saved = true;
}
catch (DbUpdateConcurrencyException ex)
{
foreach (var entry in ex.Entries)
{
if (entry.Entity is UserPL)
{
var proposedValues = entry.CurrentValues;
var databaseValues = entry.GetDatabaseValues();
foreach (var property in proposedValues.Properties)
{
var proposedValue = proposedValues[property];
var databaseValue = databaseValues[property];
// TODO: decide which value should be written to database
// proposedValues[property] = <value to be saved>;
}
// Refresh original values to bypass next concurrency check
entry.OriginalValues.SetValues(databaseValues);
}
else
{
throw new NotSupportedException(
"Don't know how to handle concurrency conflicts for "
+ entry.Metadata.Name);
}
}
}
}
}
return NoContent();
}