It is not a code in the United States ICD-10-CM.
I even double checked the CDC National Center for Health Statistics lookup tool by year going back to 2019, which is as far back as the CDC's tool goes. You can check the lookup tool here if you'd like:
https://icd10cmtool.cdc.gov/
(The CDC tool is an official source, given that ICD-10-CM is maintained by the CDC's National Center for Health Statistics.)
What sites are you seeing it on? Z72.1 was a code in versions for some countries outside the US.
If you Google Z72.1 ICD 10, it deceivingly looks as though it could be a valid code in the US. But note that Google's AI overview citations are mostly from the Government of Western Australia:
View attachment 9164
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