Solved! Go to Solution.
Firstly try to do a soft reset on your device. To do this dial *#7780# and if prompted default code 12345. If this doesn't rectify your issue try to re-install or update your current software version. To do this depending on what device you can use Nokia suite or P.C suite (once again depending on the model of your device) go in tools and software update. If not update is available re-install your current version.
You can download Nokia suite or P.C suite from the below links but if you have a fairly new phone it will be Nokia suite you need.
Let me know how you get on.