Oracle : ora-00060

Do the following:
by adding the init.ora parameters:
event="60 trace name errorstack level 3;name systemstate level 10"

Note that this can generate a very large trace file which may get
truncated unless MAX_DUMP_FILE_SIZE is large enough to accommodate the output.

When this is set any session encountering an ORA-60 error will write
information about all processes on the database at the time of the error.
This may help show the cause of the deadlock as it can show information
about both users involved in the deadlock.