Business account: Paypal.me link is not available but I can't find my handle. Where is my handle?

[verdantfield]

Setting up a payment account with a vendor and they're asking for either my handle or my paypal.me identity. Paypal.me is not available and keeps giving an error. Where do I find my handle? I have Googled this to no end and can't find it!

[kernowlass]

@verdantfield 

Your paypal email address identifies your paypal account OR your mobile number if using the app.