the problem it's present with all sm in our network. some client have a sm100, some client epmp1000, some client force 200, some client foce 180, some client sm 450.
The releas of r200 it's the last R4.
we have installed a lot of r200p and random the problem will be present in more or less in all r200p.
othe client c.a. 1200 have a mikrotik router, tplink router and similar, and the problem isn't present.
deregister SM from AP/ power off SM/power off AP/ ppp server restart
Observation :
During the test ppp session is re-established successfully and traffic is resumed. so we could not find any isssue as you reported. can u verify the issue with latest R200 version also let us know whether issue is happening always or it is reproducible once in a while.