NEW FIBRE LINE INSTALLATION

I asked for a fibre installation and for this to be activated 1 Octobe4 2021, th installation was done in September, I received an invoice dated August for full amount plus charges I cannot see because i can't view the invoice! There "super duper whatsapp chat" is frustrating to say the least, being transferred to a 3rd person now, chat has been going on for 5 hours, no resolution! Wait for an agent for longer than half hour! OMG! What have I let myself into?!?!