2007 X5 transmission NEED HELP!!!!

[03ac]

So I just did my transmission service, after starting the car I attempted to go through the gears from park, reverse, drive, etc. to allow the fluid to get through the maltronic and seloniods in order to complete filling the trans and top off the fluid. But whenever I try to put it into a gear it automatically goes back to park. I have no idea what to do at this point I replaced the 4 rubber valve body seals and the square rubber oring seal block, I can’t for the life of me remember the name of that part. I need any and all help the car was left tonight at a DIY garage where I was working on it and there charging me to keep it there over night. Thanks in advance for any help!