You may have solved this but after using 'Fuse' then use 'Weld' and set the distance a little higher. See if that works.
It would help if you could upload this file so it could be experimented on. If you do, say what version of Max you use.
Rob Holmes
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3ds Max (2023-2025), V-Ray 6.2, Ryzen 9 3950-X Processor, DDR 4 128MB, Gigabyte Aorus X570 Master motherboard, Sabrent Rocket NVMe 4.0 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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