Dear Sir,
I left China more than 20 years ago. Before I left I specifically obtained birth certification, which was recognized by USCIS when I applied for green card in 20xx and later my US citizenship in 20xx.
In reliance on such USCIS recognization of my birth certification, I did not tell my parents to keep my Chinese residential record and school record. After 20 years and several moves, neither I nor my parents have those secondary evidence you requested on XX/XX/2022.
Please find attached tertiary evidence as request because none of the secondary evidence are available. The tertiary evidences includes the following
(1) ....