When the second cleat has been validated, Increment and Decrement appear in the context toolbar to allow for modification of the cleat index.
This index is used when computing the default trajectory: the trajectory is computed from the position of the selected cleat, but the order of the cleat is also important. If a new cleat is added to an existing section of cleats, the index may be out of order as in the following example:
You can use Increment and Decrement to restore the correct order: