graph issue on cacti 1.2.3

[Mamitiana]

Hello All,
I have install cacti 1.2.3 from source on debian stretch for monitoring all our devices ~ 20 devices on cacti.Especially i need to graph bandwidh pppoe logical interface mikrotik .
Currently, i encountered somes issues on somes graphs. Some PPPoE graph work fine but for some graphs, sometimes it's graphed and sometimes there is no graphs.
Seeing from log, i meet following errors, could everyone help please to find where are the issue ?

[netniV]

That suggests its having trouble with getting the datasource information from that device. Unfortunately, due to the redactions it's hard to say much more. I would use the Data Source option under the Troubleshooting section and validate these datasources