The part in question is for organ pedal. I want to tie three 6/4 bars of dotted semi-breves but whenever I put the ties in the last dotted semi-breve cuts short by a minim. If I take the tie off, all notes get the full length. Similarly, but far worse, the next tie is five bars long but the note cuts out half way through bar 3. I tried tieing six crotchets together in one bar to see what happens and it behaves exactly as you'd expect. I'm not new to writing music but I am new to using software to do it. Help!