Railwire — Internet bill refund due to slow speed

Hi team,
I opted for railwire 9 months before for broadband speed of 100 mbps but I hardly received 30 mbps on that time. I raised with the team many times but they only fixed the issue last week. They said they will reimburse the amount for those months before but they are not responding now.please look into it and get back to me. Thank you