You are supposed to be able to have three blessings active at once, but if one of them is Death Augury, you can't. 

When you renew one of the other ones before they run out, it seems like the game counts them as 'double' and it purges the 'fourth' out of your buffs. This shouldn't be a problem, but I suspect it purges the older one active, which in most cases will be Death Augury, since it doesn't have a duration. And, since its cooldown begins when it is purged, well - it's very annoying.

May I suggest removing the timer from all blessings? It looks like an odd choice anyway, given that they reserve Warp Charge while they're active.