Auto Connect SQLConnection OpenAsync() Queue up?

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SQL-Server

I'm trying to create a wait form that will appear when sql connection is not available (ex. server shutted down / lan network disabled) the wait form will keep appearing until the connection is available again, so I don't need to keep executing query to check if the connection is available or not.
Here is what I do,

private void SQLClientLoader_Load(object sender, EventArgs e)
        {
            this.GetSQLState();
        }

async private System.Threading.Tasks.Task<ConnectionState> GetStateAsync()
        {
            do
            {
                this.cts = new CancellationTokenSource();
                this.cnn = new SqlConnection(this.par.Constr);
 
                try
                {
                    await Task.Delay(2500);
 
                    await this.cnn.OpenAsync(cts.Token);
                }
                catch (Exception ex)
                {
                    cts.Cancel(false);
 
                    this.cnn.Dispose();
                    this.cts.Dispose();
                }
            } while (this.cnn.State != ConnectionState.Open);
 
            return this.cnn.State;
        }

async private void GetSQLState()
        {
            
 
            if (await GetStateAsync() == ConnectionState.Open)
            {
                this.Close();
            }
 
            await Task.Delay(2500);
        }

This code is working, but if the wait form looped for more than 5 times, it takes a while before it close itself.
The longer the server unavailable, the longer the form will wait before it closes.
So I tried to put breakpoint inside the loop when the connection is available, it can't open the connection, it's like the cnn.OpenAsync() queue up.
Anything wrong in my code?

Note : I stop and start the sql instance service to try this code.