Big mistake. No conflict = boring to read.
So, how to add conflict? First think about the levels of conflict.
Conflict in your head - eg doubts, uncertainty, anxieties, negative personality traits.
Conflict with your body - eg ill health, physical disabilities.
Conflict with your family - eg domineering parents, disobedient children
Conflict with friends - eg rows over actions
Conflict with lovers - eg adultery, desertion, betrayal
Conflict with institutions - eg the tax office, the law
Conflict with individuals in society - eg policeman, traffic warden, doctor
Conflict with the environment - eg floods, cold weather, drought (natural) war, concrete jungle (manmade)
Now think about your main character. Going through the list, how many conflicts could your character potentially have.
For example, just thinking about the school environment a teacher could have conflicts with the rest of the staff from the groundsman to the head teacher, the staffroom tea/coffee rota, the education authority, lack of funding, Ofsted inspection, the school inspectors, exam boards, lost exam papers, marking, the government, nits, mumps, swine flu, poor weather, lack of heating, then there are the students, who may be needy, demanding, physically or mentally abusive, sad, super bright, gifted, challenging, abused, in danger...and I haven't even started on friends, family, lovers and life outside school, let alone the potential for inner conflicts.
Now I'm not suggesting that all these conflicts will have a large place in your writing, but they should be there supplying the grit that will create a beautiful pearl. Make your characters struggle against life, make life hard for them in every way, large or small, you can come up with. Isn't that why characters like Scarlett O'Hara, James Bond and Jane Eyre still resonate today? We follow their struggles and relish seeing them triumph in the end.