Dodge

I recently had my belts replaced in my car.. drove for about 30 miles afterwards and they were not making any noises. now my alternator belt sounds terrible. squeals at all times even worse at first start up. ive sprayed belt dressing on it and it stopps for about a minute then starts back up. tried wd-40 and it will make it stop for about 5 min or so and it still starts back up again.. also have tried tightening the alternater up as good as i can... no difference could this be my belt or possibly alternator? any advice would be great..thanks in advance daveit has a belt tensioner on lower end of alternator its a s tight as it can get also if i spray wd40 directly on the pulley of alternator it stops

Wd-40 will make the belt slip and squeel . i had the same car , the idler pulley its probably bad , and it is not easy to change , thats the pulley that keeps the belt tight