SWR SBC two wheeler parking Asking for more money

I have been using two wheeler parking for a long time and for the last few months they started to ask more money inspite on the board with the charges written on them kept outside.
Last week I had an argument with one of the parking staff and his answer was it’s because of GST. And today’s answer was that the tender has given to another party. I asked to change the board with whatever charged you are asking now then it would be easier for all but the answer was, it is not going to change and if you do not wish to pay then better do not come here for parking.
I have raised this issue on SBC twitter account previously but there was no response. If anything can be done to improve this, please assist which I guess can help many more who even doesn’t know the charges and give them money whatever they ask. Regards.