Voicemail Greeting

I can not record a custom greeting. I have an iPhone 8 Plus. I have tried at least a dozen times. I tried turning off wifi and turning cellular on as I saw suggested in a reply here, but that did not work. I tried that a few times after rebooting my IPhone. Everytime I make a custom recording it appears to be trying to save it and then I get an error code that reads: (com.apple.mobilephone error1035) Would appreciate help with this. Thanks.