ASP.NET Identity: Custom RefreshTokens vs Built-in AspNetUserToken

I'm currently implementing token-based auth with refresh tokens in my .NET app. Right now I have a custom RefreshTokens collection in my ApplicationUser:

public class ApplicationUser : IdentityUser
{
    public virtual ICollection<RefreshToken> RefreshTokens { get; set; } = new List<RefreshToken>();
}

I noticed that ASP.NET Identity generates an AspNetUserTokens table by default. Am I reinventing the wheel here? Could I just use UserManager's token methods (SetAuthenticationTokenAsync/GetAuthenticationTokenAsync) instead of managing my own token service? Do I need to implement my own TokenProvider?

 public async Task<LoginResponse> LoginAsync(LoginPayload request)
 {
     var user = await userManager.FindByEmailAsync(request.Username);
     if (user == null || !await userManager.CheckPasswordAsync(user, request.Password))
         throw new Exception("Invalid email or password");

     if(!user.EmailConfirmed)
         throw new Exception("Email not confirmed");

     var accessToken = tokenService.GenerateAccessToken(user);
     var refreshToken = tokenService.GenerateRefreshToken();

     user.RefreshTokens.Add(refreshToken);
     await context.SaveChangesAsync();

     return new LoginResponse(
         accessToken,
         refreshToken.Token,
         (int)(refreshToken.ExpiresAt - DateTimeOffset.UtcNow).TotalMilliseconds,
         user.UserName!
     );
 }

 public async Task<LoginResponse> RefreshTokenAsync(string accessToken, string refreshToken)
 {
     var principal = tokenService.GetPrincipalFromExpiredToken(accessToken);
     if (principal == null)
         throw new Exception("Invalid access token");

     var user = await userManager.FindByNameAsync(principal.Identity!.Name!);
     if (user == null)
         throw new Exception("User not found");

     var existingToken = await context.RefreshToken
         .FirstOrDefaultAsync(rt => rt.Token == refreshToken);
     if (existingToken == null || existingToken.ExpiresAt < DateTime.UtcNow)
         throw new Exception("Invalid or expired refresh token");

     var newAccessToken = tokenService.GenerateAccessToken(user);
     var newRefreshToken = tokenService.GenerateRefreshToken();

     context.RefreshToken.Remove(existingToken);
     user.RefreshTokens.Add(newRefreshToken);
     await context.SaveChangesAsync();

     return new LoginResponse(
         newAccessToken,
         newRefreshToken.Token,
         (int)(newRefreshToken.ExpiresAt - DateTimeOffset.UtcNow).TotalMilliseconds,
         user.UserName!
     );
 }