Had no broadband several weeks ago, engineer sent out to box outside, no issues for around a week. Now constantly have green internet light flashing. Have run test, no issues. Done everything recommended to fix issues with no change. Now finding that signal in certain rooms is non existent. Ive downloaded connect app to my phone and used that in all rooms but not helping. My son is in 4th year at school and learning from home and my daughter is in 4th year of Uni, learning from home. At the end of my tether now. Help please.