From about 32 weeks, movements stop increasing and stay roughly the same until you give birth. They may feel different as your baby grows, but they shouldn't become less frequent.
Roughly the same from here
After 32 weeks, movements stay roughly the same up until labour, and during labour too (Tommy's). The NHS week-by-week guide says the same: you should still feel your baby move at the same rate until you give birth.
Different, not fewer
The type of movement may change as your due date gets nearer (RCOG, Tommy's). Your baby may change position, so you feel kicks in a different place, or change the time of day or night when they're most active (Tommy's).
What shouldn't change is how often you feel them. What counts as a kick has more on how movements change later on.
Your baby doesn't run out of room
It's a myth that babies move less late in pregnancy because there's less space. Kicks Count, a UK charity, points out that your womb isn't a fixed size: it grows with your baby. A drop in movements is never something to put down to space.
Don't try to get a movement first
If you think your baby is moving less, Tommy's advises not trying to make them move. Even if something gets them moving for a while, that doesn't mean the problem has gone away.
Contact your midwife or maternity unit immediately if you think your baby is moving less than usual, or has stopped moving (Tommy's). Do not wait until tomorrow. What to do.