If all that was done is a fluid change--talke it back to the serviceman who did it! If an automatic has low fluid or filter in wrong, it won't go, and/or cause damage by not getting fluid where it needs to go.
If You changed fluid; check level. Add fluid as needed. If you didn't change filter, then it is not the problem, as it worked on old filter. (Best to change it with fluid, though.)
Also, look for any gross leaks from transmission. These must be addressed, too.
The condition of the fluid would be important before you changed it. The fluid might have been bad, "Burnt". which would mean your trans fluid is bad and now the clutches have gone bad also.
It is always better to change fluid often before burnt smell.
If the fluid has a burnt smell to it, then been changed out. The new fluid will further damage the transmission, ie: clutches completely smooth, no forward or reverse, etc.
check transmission fluid level bad transmission?
Check transmission fluid level.
Check transmission fluid level Perhaps needs transmission rebuild
Check transmission fluid level (auto) Change transmission fluid and filter (auto)
If the transmission would not go into gear before changing the transmission fluid, then the fluid change was for naught. Hopefully you changed the filter in there, too. If the tranny was busted before the oil change, then simply changing the oil is not going to fix the problem.
Change the transmission fluid and filter may help problem if not may have to have transmission rebuilt
Most likely causes are low transmission fluid level, dirty transmission fluid, or clogged transmission fluid filter.
You may have a broken transmission or be low on transmission fluid.
If the transmission has electronic controls, then a module could be bad. If not, then the transmission could need a rebuild. If it is a front wheel drive, check the cv joints for damage.
There's a small sensor on the transmission that the size of a spark plug.It's on the driver side of the transmission near the shift linkage
Check of change fluid and filter--if this doesn't help it may be time for a rebuild
This is commonly a problem with the transmission filter or fluid. Replace the transmission fluid or have your transmission filter taken in for maintenance.