Auto trans 46re issue

Hey all, this is not for an A body but still a mopar. I have a 99 Dakota r/t, the trans was rebuilt but a reputable shop about 4 years ago, the truck sits alot and probably only had 5 or 6k miles in the 4 years. The issue i am having started as the truck not wanting to move, free revving until higher RPMs then it catches an starts to move and will shift, it sat all winter, and i took it out this weekend, i got only 100 feet or so down the road and noticed it would not move, free revving again but would not move even under higher rpm's. i was able to limp it back home under idle.

so all that out of the way im thinking possibly a bad torque converter? interested in some other opinions. My experience with transmissions is not that extensive......lol

Thanks for any help all,

Kris