When I open an odt document with LibreOffice; microsoft word gives an error about an open dialogue box

Historically I have used LibreOffice to open .odt and Microsoft Word to open .docx documents. When I upgraded to Microsoft Office 2019 all of the writer files became assocoated with word. Then I changed the association of odt files to open with LibreOffice and now I have the problem. The version of LibreOffice is 5.3.3.2 and this is under Windows 10.
When I double click a LibreOffice file then it opens in LibreOffice but as well there is an error from Microsoft Office which says You cannot close Microsoft Word because a dialog box is open. Click OK, switch to Word and then close the dialog box and underneath is another box which says Microsodt Word isn’t your default program for editing and viewing documents. Do you want to select the file types that word should open? The same happens when I close a LibreOffice document. How can I stop this happening?

another box which says Microsodt Word isn’t your default program for editing and viewing documents. Do you want to select the file types that word should open?

What happens if you select No ?

Nothing happens - the box closes but of course opens up again the next time a LibreOffice document is opened or closed.

What other alternatives are there? Perhaps if you choose to select the file types for Word, presumable .doc* files, perhaps that would solve the problem?

It doesn’t seem to be a LibO issue.