Update OTA for custom ROM

Hi
Am on blisspop 3.6 ,over past three weeks
am getting a notification sating that updates are available
i downloaded them when I try to install the phone will reboot into
TWRP recovery and all the menu options are presented

I tried asking the same question in blisspop thread
no one bothered to answer , so am asking here
what do i do?
sorry for the noob question