A deadlock means that process A has a lock on resource R1 and is waiting for resource R2 while process B has a lock on resource R2 and is waiting to acquire a lock on resource R1.

In order to resolve it, you must change your code.

To find which resources are involved in the deadlock:
TX-000500bc-000003e3 13 20 X 18 19 S
means session 20 in process 13 has an exclusive lock (x) on resource 995 (decimal value of 000003e3)
TX-0003009a-000003e8 18 19 X 13 20 S
means session 19 in process 18 has an exclusive lock (x) on resource 1000 (decimal value of 000003e8

Simply logon using DBA account and issue:
SELECT owner, object_id, object_type, object_name
FROM dba_objects
WHERE object_id in (995,1000)
/

Cheers.