You can try doing an upgrade on the OS or replace the OS . Go tot he FAQ section at the top of the forum and use one of the programs indicated to reload the OS clean.
JL_cmdr usually is best.
How do I wipe the BlackBerry using Jl Cmder? - BlackBerryFAQ
If that does not work your BB may be defective and need service or return it to the place you purchased it if possible.