I have this problem when i try to clone

root@Ubuntu-1804-bionic-64-minimal ~ # rclone mount --allow-other --allow-non-empty -v dropbox1: /media/dropbox1 &
[1] 11525
root@Ubuntu-1804-bionic-64-minimal ~ # 2023/08/02 20:23:18 mount helper error: fusermount3: failed to access mountpoint /media/dropbox1: Transport endpoint is not connected
2023/08/02 20:23:18 Fatal error: failed to mount FUSE fs: fusermount: exit status 1

[1]+ Exit 1 rclone mount --allow-other --allow-non-empty -v dropbox1: /media/dropbox1
root@Ubuntu-1804-bionic-64-minimal ~ #

That is a problem with rclone, please ask over at https://forum.rclone.org/ .

As a passing comment, Ubuntu 18.04 is no longer supported unless you’ve bought extended support for it.

Before attempting to mount again, make sure that any existing FUSE mount points are properly unmounted. You can use the umount.

umount /media/dropbox1

After ensuring that the mount point is properly unmounted, try the rclone mount command again:

rclone mount --allow-other --allow-non-empty -v dropbox1: /media/dropbox1

If the problem persists, carefully review any error messages that appear when trying to mount. These messages might provide more specific details about what’s going wrong.