Sorting Fields on Graph Disappear After Publication

We have been running an app on Power BI for a while now and our front end charts are sorted by a specific field in order to create a progressive purple line across the chart as follows:

With the three dots on the top right corner, this data was sorted by one of the fields used in this graph, which is a line value and not an axis. Prior to publication all the options of the data to sort the graph by are available, ie:

However, on the latest version of Power BI, after publication all the sort options disappear, and only the options are limited to the two axis, ie:

And as you can see, it totally messes up the graph.  How do I get all the sort options to reappear after publication?  Any help would be greatly appreciated.  Please note that I am an intermediate level user and not familiar with coding, so please keep the advice fairly simple if possible 🙂 Thanks.....