Bengaluru Metro Rail Corporation [bmrcl] — Charged extra money

Hi, I travelled on Bengaluru metro from Hoodi to Rajaji nagar two way on Dec 16th 2023. While going to Rajaji nagar the person in the ticket counter at Hoodi station (at 11:30 am) told that the price for 2 tickets is 120 and gave 2 tokens. While dropping the token at the exit counter in Rajaji Nagar, I noticed that it showed the fare as 50 rupees instead of 60. So, in the return journey I chose to pay using Google pay and they took 100 rupees for 2 tickets and I understood that at Hoodi the person took 20 rupees extra. I am not sure if this is happening at higher level or just at the employee level. Please refund my 20 rupees and take necessary action on the employee and to end this kind of cheating going forward, please put some kind of display at the ticket counters so that the passengers can know the correct price of their ticket. Thanks.