Hi Shannon,
BAR 1
The problem here arises from the fact that two F notes have been entered. One never enters the second note to which a note is tied. Simply enter the note that follows the tie on the appropriate beat of the bar. In this case, enter E on the last triplet beat of Bar 1, Beat 3.
To correct the above, simply HOLD the DELETE KEY and right click on the second F (Beat 2). That will remove the second F and a tie will replace it.
END OF BAR 3
This is the inverse case for bar 1 above. Simply click on the E space on the first beat of bar 4. That will remove the tie because it will add a note on beat 1, bar 4.
BAR 4
What you have called a 'tie' here is not a tie. It is a slur and is entered differently than described above. I won't elaborate on that at the moment, when you get the ties under control, let me know and I'll show you how to add slurs.
Hope this helps,
Noel