Unfair deduction of R450

Unacceptable deduction of R450 from my R1000 deposit. The ridiculous charge of R450 for the drying of 4 outside cushions and 4 scatter cushions was deducted from my deposit. I am still waiting for an invoice to confirm the cost. I am sure it does not cost R450 to dry 8 cushions that were left outside by mistake and unfortunately got wet due to rain.