2 particulars numbers render the exact same result whatever the salt used ???!!!

[sdespont]

I have a big problem understanding why these 2 particulars numbers render the exact same result whatever the salt used ???!!!

        $hashids = new Hashids('any kind of salt', 10);
        $a = $hashids->encode(44888);
        $b = $hashids->encode(44900);

Result with this salt for both numbers : egjagwwPBd

It is always the same result. Is there anyone able to explain why?

I am using PHP 8.0.20 BTW

[sdespont]

Really sorry, the numbers are very similar, but different with a letter as lower case.... and my MYSQL database has been set as "case insensitive"