2002 VW Jetta has no reverse

We have a 2002 VW Jetta 1.8T and it isn’t
going into reverse. All forward gears work and
the dash highlights the R but it doesn’t move.
It will rev up like it is in neutral. We’ve checked
the transmission fluid and even put new fluid
in. Then the other day we reset the
transmissions adaptive computer and the
reverse worked for that day and then it
stopped again the next day. We tried resetting
it again and nothing, anyone have done
advice? It’s an automatic if that helps any!