battery light comes in only when its cold the night before

What is your question?

I had the alternator changed and the battery changed and the battery light still comes on. It only comes in the morning when it is cold the night before. If I stop after that and restart the car it does not come on, otherwise it will be on till I turn the car off...only happens when the temp. drops at night...if its warm at night the light doesnt come on at all...please help