Unacceptable practices

You sign a lease agreement then just charge whatever they want without notification of increases. Been a tenant for 3 months this is unacceptable anyone that can advise how I contact rental tribunal as they are changing what was on the lease agreement without notifications. Rent R6800 then communal R241 which was a surprise then now just send invoice and statement showing R288.88 for communal use and R6915 all of a sudden including a monthly admin fee Yet paid R1200 upfront for admin fee, wow unbelievable I own a ew properties I wish I could do what they are doing please can someone advise on the rental tribunal process, For those using IGrow be very very very careful