Mysql problem only in Firefox not in other browsers
I'm having a problem with mysqli update of one column. It doesn't work in firefox but works in chrome, opera and edge.
As you can see below the statement itself consist from ten different values and all the others are inserted correctly in all browsers. Problem is with the first column named wolny_zajety - it is 0 by default and it doesn't update to 1.
Here is my code:
$busy = 1;
$stmt = $con->prepare("UPDATE rezerwacje_opony SET wolny_zajety = ?, usluga = ?, opony = ?, numer_rejestracyjny = ?, marka = ?, model = ?, imie = ?, telefon = ?, email = ?, opcjonalne_informacje = ? WHERE data = '".$day."' AND godzina = '".$hour."'");
$stmt->bind_param('isssssssss', $busy, $service, $additional, $registry, $make, $model, $fullname, $phone, $email, $infofromuser);
I tried several things but nothing works. Can anybody help me?