You need to provide your User ID for customer support issues. Follow the below steps to find it on Binance website or App.
On Binance website:
Log in to your account and go to [Profile] - [Dashboard]. You'll see your User ID next to your email address at the top of the page.
On Binance App:
Tap the [Profile] icon in the top left corner. You will then see your user ID under your email address.