Validation from sqlsrv rows

[Harties]

Good day,
I am trying to validate data from a sqlserver database.
My approach is:
fields that I am checking are bit fields. Field names are the days of the week. Set to True or False in another program.
I basically want to check for the current day of the week and determine I the current day of the week matches the day and row from database and is true or false.
In my current code, below, the value of $Allowtoday changes back to 'no' after it was set true, correctly.

$Allowtoday = 'no';
$timestamp = time();
$whatdayisit = date('D', $timestamp);
while( $row = sqlsrv_fetch_array( $stmt, SQLSRV_FETCH_ASSOC) ) {
 
switch ($whatdayisit) {
 
    case "Mon";
        if($row['Monday'] === true){
            $cellno = $row['AuthorisedCellNo'];
            $Allowtoday = 'yes';
            break;
        }
        else
        {
            //echo '<dd><strong>Person not Authorised to Enter on a Monday! </strong></dt> ';
 
        }
    case "Tue";
      etc....        
 
if($Allowtoday = 'no') {
    echo "blah, blah
    exit;
 
 

rgs