PTCL BROADBAND (D-Link) MODEL NO: DSL-2750U Problem

I am having a problem in this device you see the video and tell what is happening. Same was the problem with my previous modem PTCL BROADBAND (ADSL WIRELESS MODEM) POWER 12V 0.8A MODEL NO: AN1020-25 Now I am using this below PTCL BROADBAND (D-Link) POWER 12V 1A MODEL NO: DSL-2750U DATE: May.2015