Bug with the Haste spell as a Warlock

[Pommes bio]

I just encountered a bug with the Haste spell that led to my death. I cast the spell multiple times, but my character was not under the effects of it. Moreover, even as I was casting the spell, its charges were not decreasing, even though they are supposed to be consumed unless my 'Patron' restores one.

[Sandrow]

Are you a feylock under a slow spell or trap?
Slow will deny your haste, prevent it from active.
And feylock's haste on self won't enter cold down