Sri Venkateswara Services - Agency not responding

The person who came for IFB washing machine service and he gave service for power control board and door lock replacement and he asked us to take AMC warranty services for *yrs total **** we paid for his service. Now we have a problem with my IFB machine. We called them on **.**.**** they asked us to send a bill copy and they said we will come before * PM on **.**.**** (Saturday). After we sent a bill copy they didn't respond and we tried from another number. They attended my call and said we will send a person on **.**.**** (Monday) and again they blocked our number and no response from them. So, I raised a complaint to IFB customer care. They said most of the people are doing services using the name of IFB. So, I have doubts about this service. So, I kindly request you to take immediate action for this kind of fraud service. Still we have a warranty.