Unfortunately muun won't work. It doesn't support lightning address. You can check https://getalby.com/ or https://stacker.news and use that to get lightning address and then from there you can withdraw to Muun if you want... 

 Appreciate this ty, I used Wallet of Satoshi now. 👌 

 Still have trouble, could be on my end, I'll try again.  

 From looking at your bio it looks as though you've got an onchain bitcoin wallet there. 
You'll need a lightning wallet, like Wallet of Satoshi, that'll give you an address such as 

rosyarm75@walletofsatoshi.com 

In your profile settings put this in the LN Address section and save. Hope I'm not explaining what you already know.  

 Ahh ok. I use Muun which is a lightning wallet and one of the options in the settings here. I copied an invoice address to the LN address section and saved it. Let me check if there is an email address. 👌 

 The LN address will look like an email address, you'll usually find it in 'receive' part of your wallet.  

 It’s weird. It doesn’t exist as an email address only a QR code or alphabetised code. Maybe it’s the service I chose. I’ll try another one.  

 I changed wallets to wallet of satoshi and linked them! This should now work. Haha EU law, what EU law!!  

 Perfect, welcome to zaps ⚡️ 

 Thank ya kindly 👌 

 I changed a setting on Muun, it was already set to satoshi but I had receives set to a new format that’s not widely supported. I’ve changed that to lightning. Hopefully should work now.  

 Nah, still won't work. I don't think an invoice will work, you need an LN (lightning network) address.