Discovery Health placing me under financial constraint due to large excessive premium deducted.

I submitted documents of proof of income (SASSA account bank statement and my personal bank statement) for Keycare plus - as I only receive State old age grant and am a widowed pensioner., however this month you deducted an amount of R3354 instead of the normal premium of R1489. I have called and mailed man, many times and have received absolutely no feedback. This places me under severe financial constraints for the month as I only receive SASSA old age grant. This is really verry stressful and terrible service from Discovery