Problem with gloves - don't giveing me bonus

Hello. I have problem with my gloves. I bought they from some player. This gloves don't giveing me bonus to spell damage.

Name: Doedre's Tenure Velvet Gloves
Energy Shield: 28
44% increased spell damage
+10 inteligence
+16 max energy shield
20% reduced cast speed

When i have equiped this gloves my spell's have:
-Fireball: 245,3 DPS
-Firestorm: 283,5 DPS
-Freezing pulse: 430,9 DPS

When i haven't equiped this gloves my spell's have:
-Fireball: 232,9 DPS
-Firestorm: 281,8 DPS
-Freezing pulse: 438,5 DPS

I think this gloves have some bug.

how much added spell damage do you have on other items and passives?

also...even though you have the added 44% with the gloves the reduced cast speed will remove some benefit from the overall total dps

Don't think so. MY freezing pulse have like 440 DPS. 44% of this is + 100 DPS. 20% reduced cast speed can't gain 100 DPS... its only like 0.10 sec slower casting...

My totem don't get spell dmg bonus too and i think totems dont have lower DPS when cast time is slower or faster.

That's a level 14 freezing pulse, 101 to 151 damage per cast so even it out and say average 125.
that before any modification.
if all you have is the 44% spell damage on that set of gloves and nothing elses that would be
125 +44% = 180 average factor in the cast speed would give you 243 dps on average.
now adding the penalty on the gloves makes your cast speed 0.78 giving you a total of 219.6 dps

unbuffed average 168.75 dps
Average with added spell damage 243 dps
average with spell damage and cast speed penalty 219 dps

now i'm not sure how added cold damage is calculated but spell power is pooled, you could have another 100% from gear and passives and adding the gloves gives you a total 144%.