messages notifications.

Hi All, not getting any on screen notification of incoming texts or text tones, I only see them if I check, with a couple of my contacts also when there isn't a blue dot on the left hand side to indicate a text (on the messages page) there is a random white one with grey shading? also worth mentioning when there ARE blue dots on these particular contacts they are of a different style.

How would I go about rectifying this? as one of the contacts is my other half and **** hath no fury like a woman waiting on a reply!

Many Thanks

Mozz x