Bad LTE Signal

I would like to cancel my LTE service with Telkom. I receive very very poor signal and have been complaining for the past few months to telkom. Eventually Huawei sent a technician and he confirmed this. Their solution was to install an antenna but my body corporate won't allow this. I filled out the cancellation form but have got no response yet! According to the telkom website I should receive LTE signal but this is obviously a lie! Also for some reason I am being charged a migration fee every month when this was supposed to be a once off cost.