Guild Wars 2

I was under the impression that if veteran players pre-purchased Heart of Thorns Ultimate, they would get two additional character slots, one for buying the ultimate package and one for pre-purchasing as a veteran player.

I only got one additional slot. Why is this?

When did you register your upgrade? If you registered it prior to today, July 10th you should have received the loyalty slot today. If you registered today they will be sending them out in stages:

https://help.guildwars2.com/entries/94582027-Heart-of-Thorns-Pre-Purchase-FAQ

All accounts that become eligible by July 9 will have their free character slot applied by July 10. Eligible accounts that are upgraded with a pre-purchase serial code after July 10 will receive their slots on a weekly basis after that.