Ok i figured what happened. There is a problem, that when you have double connections configured like me, you can't specify two gateways by gui. That makes problem that openwebif can't read second gateway and shows errors. I tested openwebif and old webinterface and same problems. Could devs make something to repair this? As i remember it works some long time ago on older pli builds.
I have double network configuration. Wired and wireless. Both ip works. Yesterday tried fresh install pli image. Nothing changed. It looks like some python libs problem.