iptables list command with very verbose option

Can someone explain the meaning of the following error messages that are generated from running the iptables list command with the very verbose option, i.e. iptables -Ln -vv? The error is highlighted below with the arrows.

The error is generated for every custom 'Target name' used in the iptables script. The iptables list command with the -v option does not generate any error messages and the script 'appears' to function properly. I have a basic understanding of iptables, though I haven't seen any documentation that explains the very verbose output (and I'm not a programmer). I have googled "Target name: `ERROR' [64]" and it appears the last block containing "error='ERROR'" is commonly generated from other people's scripts, though I haven't seen any mention or concern about the error message itself. Any help is appreciated.


=========================OUTPUT=====================
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.
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SRC IP: 0.0.0.0/0.0.0.0
DST IP: 0.0.0.0/0.0.0.0
Interface: `'/................to `'/................
Protocol: 0
Flags: 00
Invflags: 00
Counters: 0 packets, 0 bytes
Cache: 00000000
Target name: `ERROR' [64]<<<<<<<<<<
error=`IN_ACC'<<<<<<<<<<
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SRC IP: 0.0.0.0/0.0.0.0 *****LAST BLOCK*****
DST IP: 0.0.0.0/0.0.0.0
Interface: `'/................to `'/................
Protocol: 0
Flags: 00
Invflags: 00
Counters: 0 packets, 0 bytes
Cache: 00000000
Target name: `ERROR' [64]<<<<<<<<<<
error=`ERROR'<<<<<<<<<<

=====================END OF OUTPUT==================