After 146 minutes wasted on the most frustrating calls of my life

Where does one start with the most frustrating communication and poor service ordeal I have ever known!
After 146 minutes of wasted time phoning Jetstar’s 131538 so called customer service numbers, not one thing has changed.
After falling ill with Gastro which I did not wish to share with airplane passengers, 36 hours before my departing flight, I called that dreaded number and to start was waiting on hold for 30 minutes. Already suffering a massive headache, fever & seriously sleep deprived, but wanting to notify Jetstar of my need to cancel my flight tickets ( I knew of people who wanted a seat on this this flight). I persisted even though I could understand this lady’s accent. I was told I may qualify for a refund on compassionate grounds if I had a doctor’s certificate and was advised to call back once I had that. ( getting a cert was frustrating enough having to ask for a second as the 1 st was hopelessly worded).
2nd phone call -a 15 minute wait. Another person who I can barely understand says ‘who told you you could get compassionate leave you don’t qualify for that.’ Grrrrrr. And she suggested I try my travel insurance (IMPORTANT NOTE- travel insurance requires proof of cancellation). So I asked customer ‘service’ to email me a letter saying the departing & return flight tickets were BOTH CANCELLED by myself over this phone call. She responded that she would.
No email -and NEXT DAY I start receiving ‘reminder to check-in’ SMS notifications. What!!!
So PHONE CALL 3 the guy goes through the whole phone ‘process ‘ again and I would lose money if I didn’t fly. By this time My departing ticked was marked as a NO SHOW( which they can’t change)I explained I understood but I Can’t fly from QLD to Victoria because I’m STILL IN VICTORIA 🤦🏽‍♀️& I simply wanted to cancel my tickets and have it in writing.
After putting me on hold numerous times (he was probably just taking a coffee & pee break !)
He said he would cancel my tickets - again I emphasised that I wanted an email confirming this for both flights. He said he would send one shortly.
NEXT DAY & prior to the RETURN FLIGHT time -STILL NO EMAIL and further ‘check-in’ SMS. Notifications - what the heck! I am so irate (& this is not me) I call a fourth time - respectfully angry like a simmering volcano!
The lady goes through the whole process AGAIN this lady’s English is worse than the last two. Jetstar’s aim is to really p*s* people off and deter them from pursuing a refund. ANYWAY, in this call she tells me I can have replacement ticket vouchers - I state ‘I WAS NEVER OFFERED THIS ANY TIME DURING THE LAST 3 phone calls !!! I may have even accepted but due to the disgusting service I said to her I wanted it noted that I will NEVER fly Jetstar ever again and will tell all my friends NOT TO also.
I request AGAIN AND AGAIN that she send me email confirmation there stating that I had cancelled BOTH my flights. And that I was NEVER offered vouchers TIL THEN. She stated what she was putting in the email and I asked her to send it- she promised she’d do it after the call- GUESS WHAT NO EMAIL. I am so frustrated. This has to literally be an organised scam business. RANT OVER
I WILL TRY THE NUMBERS ABOVE AND SEE IF I GET ANY WHERE FURTHER.

Domestic
Australia-Melbourne - Tullamarine
Australia-Sunshine Coast