Liftedchevy207

Hello I have an 03 Chevy Silverado. And my truck feels like it don’t wanna shift for a few seconds into second when I get right in and go. If I wait and let truck warm up for a few mins it’s fine. It does this every time. But ones I get right in and drive and it does that shifting problem it only does it that one time till I turn it off and let it sit for a while. Hopefully it makes sense and someone can help me