Unacceptable Premium increase and lack of communication

I have emailed Budget Insurance three times to advise that my premium increase of 20% is unacceptable and needs to be looked at. My problem is that I am overseas until the end of May and only have access to emails and WhatsApp. I am unable to make or receive calls. I did convey this in all of my emails, however I am still waiting to hear back. All I am getting is acknowledgements of my emails and that someone will contact me within 24 hours! My first email was sent on the 8th April, which was a week ago!.