Datum Transformation cannot be found

[AdelmoCos1]

I upgraded ArcGIS Pro from 10.8 to 10.8.1. When opening existing layout  created from ArcGIS Pro 10.8, the message below pop up every time I open up any layout created from older version.  

I tried to fix the issue but the second transformation shown below cannot be edited.

Any suggestion to fix the issue would be greatly appreciated. 

[TI]

This issue appears to have disappeared with version 3.x (not sure which version exactly).  It is not present in version 3.3 (for me), and was not present in version 3.2.  I can't remember for sure about 3.0 or 3.1.