Hi <firstName>,
Thanks for your email.
I've been ill with the cold so I'm just reading your email.
I'm very excited to have received an internship offer and I'm happy to accept it.
As explained on the phone apologies for being unable to meet up today, I was sick and spent this morning/afternoon getting and setting up my new phone which I ordered after our video chat yesterday.
I look forward to out meetup tomorrow,
Kind regards,