也许我没有正确理解您的问题，但如果您需要将另一部以字母为字母的手机更改为按字母/数字模式的数字2(A,B,C) 3(D,E) ,F) 4(G,H,I) 5(J,K,L) 6(M,N,0) 7(P,Q,R,S) 8(T,U,V) 9(W,X) ,Y,Z)你可以试试这个：

$another_phone = 'holidays1';
$alias_array = array(
    '0' => ['0'],
    '1' => ['1'],
    '2' => ['A','B','C'],
    '3' => ['D','E','F'],
    '4' => ['G','H','I'],
    '5' => ['J','K','L'],
    '6' => ['M','N','O'],
    '7' => ['P','Q','R','S'],
    '8' => ['T','U','V'],
    '9' => ['W','X','Y','Z']);
    
$phone_in_letters = strtoupper($another_phone);
//creating an array
$phone_in_letters_array = str_split($phone_in_letters );

$phone_array = [];
foreach($phone_in_letters_array as $val) {
    foreach ($alias_array as $key => $letters) {
        if (in_array($val, $letters)) {
            $phone_array[] = $key;
        }
    }
}

print_r(implode($phone_array));