Printer loses connectivity after changing SNMP <Public> community name

When changing the SNMP <Public> community name, our RICOH Aficio SP C830DN printers lose their connectivity and go offline, EXCEPT ONE. That is the mystery. There is another RICOH Aficio SP C830DN almost next to the one that works, but it goes offline and when I did a side-by-side comparison of each printers configuration, the only discrepancy was in firmware versions and that the working printer's factory name had not been changed. Another printer with a higher firmware version had also gone offline, so I'm currently ruling out outdated firmware as a reason as to why all these printers go offline, except that one. And not being well versed in SNMP, I'm a little puzzled.

Is there a check list I should go through to identify what the working printer might 'being doing right', as opposed to the others. I'm also thinking there is a switch issue in here that I haven't considered, except all printers are on the same subnet.

Thanks in advance for any help.