[Rspamd-Users] Script attempted to access nonexistent global variable 'cjson'

[C. Bernard]

Hi all

for a few weeks now, I get every minute in the log:
2020-01-25 17:53:00 #23402(controller) <ndniuo>; lua; neural.lua:1142:  
cannot exec invalidate script in redis: ERR Error running script (call  
to f_a43800941e2820ed8d764d50dfd9c142beddde68): @enable_strict_lua:15:  
user_script:6: Script attempted to access nonexistent global variable  
'cjson'

Any idea what I could do to make that go away?

Thanks
cmb