You keep leaving a gap in that piece.
It's where you stop and have a think.
Where you can't find the next notes in time.
Sometimes, you grind to a halt right there and leave the room.
Take heart - try only the pesky group of notes as slowly as you can.
Check the fingering or placing on your instrument first.
Move smoothly between each note.
Replace the rhythm, still playing slowly.
Speed up a little each time.
Bravo - finish your session by playing a favourite piece. Hz