So lately I've seen a lot of verified bots using the new "Unix Timestamps". But when I try <t:${message.author.createdTimestamp}> it somehow outputs the 50000th year, lol. So that's the problem.
I will really appreciate any form of support because that problem seems controversial to me.
Maybe there is some package or method which can solve this issue. Sadly, I don't know what it is.
It looks like <t:###> will accept seconds only and the timestamp is in milliseconds. You'll need to divide the timestamp by 1000 and as it only accepts integers, either round it (using Math.round(), Math.floor(), etc.) or convert it to an integer (using parseInt()).
Any of these should work and display the date correctly:
<t:${Math.round(message.author.createdTimestamp / 1000)}>
<t:${parseInt(message.author.createdTimestamp / 1000, 10)}>