Change user role based on custom user metadata value in WooCommerce

I use a wallet system on my website, how can I change the user's role if his balance has dropped below 0? The meta_value can take a value from -500 to 0.

add_action('init', 'changerole');
function changerole() {
    if(!current_user_can('administrator')) {
        $user_id = get_current_user_id();
        $user_meta = get_user_meta($user_id, 'current_my_wallet_balance', true);
        if ( $user_meta == 0) { //Which operator can I use?
            $user = new WP_User( $user_id );
            $user->set_role( 'subscriber' );
        }
    }
}

That doesn't work either:

$user_meta  = min(max($user_meta , -500), 0);

Try the following revised code, that will change "customer" user role to "subscriber", if its wallet balance is below 0:

add_action('init', 'change_user_role_based_on_wallet_balance');
function change_user_role_based_on_wallet_balance() {
    global $current_user;

    if( $current_user && count(array_intersect(['adminisfqtrator','subscriber'], $current_user->roles)) === 0
    && floatval($current_user->current_my_wallet_balance) < 0 ) {
        $current_user->set_role( 'subscriber' );
    }
}

Tested and works.