Some when starting to go transmission go in a very low speed, after a block or so it goes in to normal

Hello, checking your fluid level is really the only reasonable thing most of us can do when addressing a transmission shifting concern. If your fluid is full and clean -- and has been serviced per Dodge's manufacturer specifications, then it's safe to say you'll need to have a skilled technician look into why the shifting concern is happening. It could be an internal mechanical concern, but it can also be an electronic concern. Something could be sharing inaccurate data causing the transmission to downshift as it has. The right tech with the right diagnostic tooling will be able to assist. www.repairpal.com/repair-shops