The correct order for bond angles is:

In  NO2+, there is no lone pair, only bond pairs so the molecule is linear leading to a bond angle of 180°.In NO2, the one lone electron exerts a less repulsion than a lone pair of electrons, so two bonding   oxygen atoms are able to spread out more leading to bond angle greater than the ideal of 120°.  For NO-the molecule is bent but we have 1 lone pair on nitrogen. Lone pair electron repulsion is more than the bonding electrons so the bond angle will be less than  120°.