Join Geometry is no longer removing lines between walls and floor

[sevendaypermits]

Recently RevitLT 2020 stopped eliminating the lines between elements I am trying to join:

I can use the Linework override and select each line, make invisible, but I am not sure why the Join command is no longer doing this.  The image below shows an example, the right side shows the walls and floor system, I used to be able to select join, pick the wall and floor and it would remove the lines of the floor (as is shown on the left side of the image).  Currently, nothing happens when I select join, the lines of the floor are still visible.  The left side of the image showing the lines of the floor removed is achieved by using the linework tool, selecting each line individually.  

Any thoughts would be helpful, selecting each line and making it invisible is time-consuming and time is money!

[barthbradley]

Play around with Switch Join Order.

...another thing you can do is to align surfaces in 3D View using the Align tool.

[ToanDN]

Unjoin them, paint the egde of the floor with the same material of the wall finish, join again.

[mauricio_mssf · Accepted solution]

Check if the material of the wall and floor are the same, to join without lines it must be the same material, these lines can be of different materials but with the same graphic representation.

Another option is that the floor outline is not aligned with the wall, perhaps by changing the type or thickness of the wall, or moving.

[barthbradley]

.

[sevendaypermits]

Appreiciate the comments, I have tried both of those, still the same result that the lines between the floor and wall are still visible.

[sevendaypermits]

This does technically work, the comment below yours about making sure the base materials of the assemblies is the better option so that all base assemblies have the same finish, then they can be joined.

[sevendaypermits]

Beauty!  Making sure the materials are the same.  There was a comment above similar to yours about painting each element, but ensuring the base materials are all the same works.  I just made sure that each new element has the same "default" material, now merge works.