Unhandled exception (#707f4184)

[sqlmapreporter]

Running version: 1.4.7.5#dev
Python version: 2.7.18
Operating system: Linux-4.4.0-18362-Microsoft-x86_64-with-Kali-kali-rolling-kali-rolling
Command line: sqlmap.py -u ******************************************************************************************************** --dbs --random-agent --technique EUS -p no --level 5 --risk 2 --tamper=space2comment --batch --answers=******************** --tables -T ******* -C ****************************************** --search --time-sec 30 --timeout 10 --retries 3 --hex
Technique: UNION
Back-end DBMS: Firebird (fingerprinted)

Traceback (most recent call last):
  File "sqlmap.py", line 215, in main
    start()
  File "lib/core/decorators.py", line 75, in _
    result = f(*args, **kwargs)
  File "lib/controller/controller.py", line 704, in start
    action()
  File "lib/controller/action.py", line 179, in action
    conf.dbmsHandler.search()
  File "plugins/generic/search.py", line 627, in search
    self.searchColumn()
  File "plugins/generic/search.py", line 458, in searchColumn
    tbls = tbl.split(',') if not isNoneValue(tbl) else []
AttributeError: 'list' object has no attribute 'split'