I was given reduced loot on titan for not being in the alliance when the titan spawned but I was there 38 minutes before it spawned.
Did you get the titan loot within 20 hrs of another titan loot? You can check in your Recent activity.
In recents, the next previous titan rewards were given a day ago.
Okay. Well, if you feel it is a bug then definitely submit a support ticket from the in-game menu options. See #contact-support if you need any help.
There is a 20h rule. When you switch alliance and you pick up titan loot within 20h of the previous titan loot it will be reduced. You can avoid the reduction by just staying ofline and let an alliance member check your join time. Once it hits 21h you can login again (I didn’t dare to try 20h because of possible rounding).