I tried to create a new gmail address recently because my primary gmail address is my name, and it's quite common, so I get more email for other people than I get for me.
My phone number - which I've had for about 15 years and have only ever used for personal purposes (minimal SMS, mainly just an iMessage/Whatsapp ID) - is apparently "not eligible" to create a new gmail account. Which is quite strange.
If this is with a new android phone, return it and let the manufacturer know why you couldn't use the phone.
For something as central as a Google account, it feels pretty unreasonable that a long-held personal number can be silently rejected with no appeal path or explanation