Upload Failed: Your file was not uploaded because your changes can not be merged with changes made by someone else error for Excel and PowerPoint in MS Office 1903 build

Hi,

We have office integration implemented in our application using Office URI Schemes for editing server files.

For Example: ms-excel:ofe|u|https://path_to_file  for editing the server office files.

Steps: i) We form the above webdav URL

           ii) Handover the URL to OS to open the corresponding office application.

           iii) Make changes in office files and then save it which saves the changes to server.

Problem: We have our user facing issue while checking in any office files(saving to server) i.e, user is facing issue while saving the modified office file after checking it out.

The file opens in "Protected View", user clicks on "Enable Editing". Then user modifies the file and clicks on Save.

                 > For Excel an error message "Upload Failed: Your file wasn't uploaded because your changes can't be merged with changes made by someone else" pops for excel.

                > And for PowerPoint an error message "Save Again: We need to refresh your file with updates.Click save to try again."

We have performed "office Upload Center" cleanup activity and also office repair following the blog . But still face the issue. 

Note: 1) The same works for MSO Excel 1808 build version but not in 1903 build which the user is using.

         2) File is not shared with any other user( mentioning this as we came across that co-authoring may cause this issue)   

            3) Once the user clicks on "Discard Changes"  and modifies again , then the file saves properly. But yet this will be a workaround but not a permanent fix   

Kindly suggest if we are missing anything from application end or any changes that we need to incorporate ?

Thanks In Advance
Radhika