org.cryptomator.common.vaults.Volume$VolumeException: Unable to mount Filesystem
at org.cryptomator.common.vaults.FuseVolume.mount(FuseVolume.java:52)
at org.cryptomator.common.vaults.FuseVolume.mount(FuseVolume.java:41)
at org.cryptomator.common.vaults.Vault.unlock(Vault.java:142)
at org.cryptomator.ui.unlock.UnlockWorkflow.attemptUnlock(UnlockWorkflow.java:107)
at org.cryptomator.ui.unlock.UnlockWorkflow.call(UnlockWorkflow.java:90)
at org.cryptomator.ui.unlock.UnlockWorkflow.call(UnlockWorkflow.java:44)
at javafx.concurrent.Task$TaskCallable.call(Task.java:1425)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)
Caused by: org.cryptomator.frontend.fuse.mount.CommandFailedException: ru.serce.jnrfuse.FuseException: Unable to mount FS
at org.cryptomator.frontend.fuse.mount.MacMounter.mount(MacMounter.java:48)
at org.cryptomator.frontend.fuse.mount.Mounter.mount(Mounter.java:8)
at org.cryptomator.common.vaults.FuseVolume.mount(FuseVolume.java:50)
… 12 more
Caused by: ru.serce.jnrfuse.FuseException: Unable to mount FS
at ru.serce.jnrfuse.AbstractFuseFS.mount(AbstractFuseFS.java:293)
at org.cryptomator.frontend.fuse.mount.MacMounter.mount(MacMounter.java:46)
… 14 more
Caused by: ru.serce.jnrfuse.FuseException: Unable to mount FS, return code = 1
at ru.serce.jnrfuse.AbstractFuseFS.mount(AbstractFuseFS.java:289)
… 15 more
Hey and welcome to the Cryptomator Community 
,
Pretty limited information you provided but maybe this will help: