Recovery / Safe Mode on bootlooping Kyocera KYF42

Hello everyone, for the last few days my Kyocera KYF42 has been bootlooping. I don't know what could have caused this, but I would like to have my phone back. I've heard that some Kyocera phones can enter a Safe Mode when holding the side button and enter key whilst booting, but I've had no luck with that on mine. Some others have suggested entering Recovery Mode by holding down the Star key when booting, but when I did that all that would happen was that the device would skip the AU carrier screen and loop back to the Gratina screen. Elsewhere I've heard that the battery might cause a bootloop if it's failing, but I'm not sure about that. Do any of you have experience with this? Or any other suggestions? I'm open to trying things that work on other similar models of Kyocera keitais.

Thanks in advance!