After following the setup correctly, the timeline was only showing a single line and not displaying the data as expected. After investigation, I discovered this was because I am using Next14 which is not fully compatible with the timeline package.
Steps Taken
After researching online, I found if you set the variable "visible" to true, then the data would show although this then led to the animation not working.
I found a solution which sets "visible" to inView from the react-intersection-observer and this then fixed the problem I was having.
Steps Taken