Billing issues/poor service/ terrible network coverage

Ordered 1 new simcard, 2 were delivered and I got billed twice. Issues with cancellations and refunds. Poor service and little to no support from department, as well as late/ no responses from emails. Malfunctioning website/platform that directs me to login page when trying to cancel/change details. In addition to this, the network coverage is so bad, I have to restart my router several times in a day.