Incorrect Formatting of Timeline (from a Template)

I'm having issues with the layout of my chart's timeline. It was provided by the template [i.e., original milestone chart] that I usually have issues with, but can't seem to resolve the issue alone this time.

Excel Version: Office 365

Type of Problem: Chart Formatting

The dates shown do not align with the input given as it shows monthly period instead. Additionally (or probably as a result), the phases also overlap. It has been possible to show the respective dates as shown in the picture below. I don't have the file version shown below, unfortunately.

File in Question: Prod Schedule.xlsx
Template Being Used: Original Milestone Chart - Copy.xlsx

Origin of Template: https://www.mastt.com/resources/milestone-chart-excel

It should look like this.

How can I resolve this issue?