if not then:
launch novetus
then click option
then click on novetus SDK
double click asset SDK
then use btroblox extension to download the model
then in asset fixer choose the type of asset choose rbxm
click browse and localize model/place and then click on that arrow ^ but it facing the other way (arrow thats is nearby with text "name of file") and then find direction C:\Users\"your username"\Location of model file (for me it download)\18404267.rbxmx (name of this model file) then choose it and press open
asset is should be fixed
edit: i tried it and it working! (it didnt worked but it was because i choosed bak file (idk what is this) instead of fixed