Rain Internet Service Provider

They want to charge me for the **** service I received the pass 5 months i paid for 4 months while sending numerous emails about the speed I got which they never resolved but the 5th time I refuse ... you cant promise people speeds of up to 10mbps and then we get under 100kbps but my signal is full and you expect us to pay full price??? the worst provider ever I can help them fix their ****py Service for the right price if they willing to spend