Splitting tax code

Last year I split my tax code since I receive pension income and self employed income. I did this using web-chat. This year I have a new tax code and again need to split it. I have searched high and low on hmrc app and online and there is no way to do this except by -'adding another employer'. I have already tried web-chat and I am constantly told that no-one is there or the webchat will not load, despite the fact that this service should be available until 8pm

Hi,
To split your allowances you will need to contact our helplines, as this facility is not yet availabe on the HMRC App -
Please see link below for ways to contact
Income Tax: general enquiries
Thank you.