Missing data and Airtime

after that huge mess up where peoples data went missing over night i haven't had peace with my data and airtime, the billing is just not right ,on both my phones data goes missing like a kid eating sweets. i had 689mb yesterday this morning i get a message stating i have 234mb left nothing was running on my phone overnight but data goes missing just like that , now i bought airtime of R20 sent one sms of R1.50 ansd all of a sudden i am left with R3, can someone please explain this to me urgently call has been logged already but my data is finishing cant wait for 48hrs