D-Link plug seen offline after a couple of days

Hello from a newbee

I have setup OH2 on my raspberry a few weeks ago, initially started to try to use my D-Link plugs thanks to some scripts found in various blogs / forums with some limited success.
Then I noticed about a couple of days ago that there was a binding available for those plugs.
I started to use it and was almost immediately able to switch on/off the plugs but did not get any figure shown regarding power or temperature.

1st question: Am I supposed to write some rules for the power / temperature … to get updated?

Then today, I wanted to use the switch again and got the message “plug offline” (same thing for the 2 plugs)
Below the log of the error.

2017-11-15 19:33:50.277 [ItemCommandEvent ] - Item ‘DSPW215’ received command ON
2017-11-15 19:33:50.290 [ItemStateChangedEvent ] - DSPW215 changed from OFF to ON
2017-11-15 19:33:50.301 [ERROR] [e.internal.WriterInterceptorExecutor] - MessageBodyWriter not found for media type=text/event-stream, type=class org.glassfish.jersey.media.sse.OutboundEvent, genericType=class org.glassfish.jersey.media.sse.OutboundEvent.

Firmware External Version: V2.22
Firmware Internal Version: V2.22b05

At this stage, if I connect directly to the plug IP, I get the normal menu but even after entering the right password nothing happens. As if the plug is frozen… but the plug is still responding to the D-Link app!

Last step, if I reset the plug (taking it off the main and back in)… I can again control the switch from OH.

2nd question: any idea what to do to avoid this loss of control from OH after a few days (it sounds like the issue would be more on the plug side… or something to do with token authentication refresh?)

Thanks for those who will be able to help!

Vincent

Regarding 1st question, at least I could identify one issue: Power and temperature come as a string, not a number as I first thought.
But even after changing the formating, for the moment no update, even if I can see in the log that values are being updated.