Solved Boolean returning as false.

I've integrated a Heads Up Display into my Core plugin. The HUDs are of two types: Normal (for players) and Staff (for the staff). The staff's names have been hard-coded into the core.
Here's the code:
Function in the API:

PHP:

public function isStaff(string $player) : bool {
    $staffs = [
        "RumDaDuMCPE",
        "RoyalMCPE",
        "FireRage5520",
        "ManXmaster27"
    ];
    foreach ($staffs as $staff) {
        strtolower($staff);
    }
    if (in_array(strtolower($player), $staffs)) {
        return true;
    }
    return false;
}


The task that calls the function after checking if the player is staff or not:

PHP:

    public function onRun($tick) {
        if ($this->core::getInstance()->getAPI()->isStaff($this->player->getName())) {
           $this->player->sendPopup(TF::colorize($this->core::getInstance()->getAPI()->sendHUD($this->player, "Staff")));
        }
        $this->player->sendPopup(TF::colorize($this->core::getInstance()->getAPI()->sendHUD($this->player, "Normal")));
    }
}


File containing the sendHUD Function:

PHP:

public function sendHUD(Player $player, string $HUDtype) : string {
    $playerCount = count(Server::getInstance()->getOnlinePlayers());
    $playerMax = Server::getInstance()->getMaxPlayers();
    $color = "&a";
    $tps = Server::getInstance()->getTicksPerSecond();

    if ($tps < 20) {
        $color = "&c";
    }

    $staffHUD = "&l&a".$player->getName()." &r&l|&r &e".$playerCount."/".$playerMax." &r&l|&r &bTPS: ".$color.$tps."\n".
    "If TPS is below 20 for a long time, let Rum know.";

    $normalHUD = "&l&b".$player->getDisplayName()." &r&e| &l&a_ingameMoney_"."\n"
        ."_playerVoteStatus_";//$this->getVoteStatus($player);

    switch ($HUDtype) {
        case "Staff":
            return $staffHUD;
            break;

        case "Normal":
            return $normalHUD;
            break;

        default:
            return "&cERROR FETCHING HEADS UP DISPLAY!";
    }
}


The issue occurs when I use a username that has been hardcoded as staff and yet I receive the normal HUD meant for the players.

Kindly help me find a solution to this issue, Thank you.

UPDATE: I have found the solution. I forgot to call an Else function after the If function in the Task.
Updated code:

PHP:

    public function onRun($tick) {
        if ($this->core::getInstance()->getAPI()->isStaff($this->player->getName())) {
           $this->player->sendPopup(TF::colorize($this->core::getInstance()->getAPI()->sendHUD($this->player, "Staff")));
        } else {
           $this->player->sendPopup(TF::colorize($this->core::getInstance()->getAPI()->sendHUD($this->player, "Normal")));
        }
    }
}