.mbtiles output missing bounds

I am trying to output a .mbtiles file. It appears in the …Pix4D\filename\3_dsm_ortho\2_mosaic\google_tiles file extension but when I try to open it in MapTiler it says that the file is missing bounds value in metadata.

I think .mbtiles are optimized for MapBox.com, not MapTiler.

MapTiler works fine with GeoTIFF.