The WORST service experience I have had in 67 year...

The WORST service experience I have had in 67 years of life spanned across 3 countries!!!! I have a modem problem with NBN broadband service. They tell me 3 month old modem is faulty. They "order" a replacement.... or so they assure me. Long story short....ended up driving to Perth iinet store to fetch a loan modem because they failed to order the modem as promised.....3 times....each time I had to follow up after a few days between each call... they NEVER called me or informed me what progress was! EACH time they promise and then ....do NOTHING!! Escalating my complaint also had ZERO effect. STILL awaiting modern replacement delivery. Now I get a message threating charges in excess of $100 if I do not return loan modem because I am keeping it too long..... but I still have no replacement modem. Left hand does not know what the right hand is doing...
EVER! Cannot wait for my contract term to finish ... there will be a BIG vacuum behind me as I run to cancel the contract! These issues on top of continued billing over charges at time of connection..... charges which they NEVER resolved and i ended up giving yip....toooooo hard.... they wore me down and won!
Now these issues 3 months after signing up with them.
Problem still unresolved.... and they do not appear even to have sufficient pride in their brand to care a hoot what a customer experiences.... or when they get bad press or review. Unbelievable!!!! Feels like talking to a big black hole....... telephone Customer technical service reps in Cape Town VERY friendly and nice.... but NOTHING happens to your problem or complaint!