malaysian airlines - airlines scam to take extra money

I have booked a round trip from Bangalore to Penang which had layover in Kuala lampur. In Kuala lampur, i missed connecting flight as immigration officer took longer time to allow me inside. I asked Malaysian airlines to offer me alternative flight to Penang, but they denied my request and asked me to pay penalty of **** INR. They were so rude in response. I took bus from KL to Penang as they didn't offer me alternative flight. After few days, when i came to take return flight from Penang, they denied my boarding and asked me to reach to customer care over phone and there was no one to support in person in the airport. I contacted customer care and agreed to pay penalty. But they intentionally kept me on hold to ensure that i miss my flight from Penang. After keeping me on hold for ** mins, they said they can offer next day flight, but i have to pay additional penalty plus differential flight charge of ***** INR/person. I missed my flights because of them and they intentionally did that to take additional money from me. It was clear cut scam from them