Tasks NOT obeying or following predecessor relationships constraints in Gantt chart

I spent 3 1/2 hours searching for answers and trying to figure this out.  Now that I have a simple answer, I wanted to share it.  Anna in Wrike Support helped me solve it.

If your tasks are not following the predecessor dependencies, then do the following.

Check for "Start Constraints" on your tasks, or add, remove, and edit date constraints on the table portion of the Gantt Chart.

1. Select a folder or a project from the left-hand navigation panel.
   
2. Switch to the Gantt Chart.
   
3. Click the gear icon at the top left of the table portion of Gantt Chart, right above the task numbers.
   
4. Check the “Start Constraint” checkbox in the pop-up that appears.
   
5. Click anywhere outside the window to see the new Start Constraint column in the table.
   
6. Find the needed task and CLEAR the date constraint in the “Start Constraint” column so that it will obey the predecessor.

Your tasks will once again follow their predecessors and behave as you would expect them to.

What causes these constraints to get entered when you didn't do it?  It can happen sometimes when changing duration of tasks that are in a linked dependency chain (what happened to me), or it will happen when you manually drag task bars on the Gantt chart view.

I hope this helps someone.