I'm receiving an error

I'm receiving an error "You need to provide additional information. Please correct the errors below and try again. Go to Account details". After clicking "Go to Account details" there's no indication of what information needs to be edited/updated/removed. Another thing is the contact list where I will select which list to send the email is not showing before sending the email. Tried "send now" and "schedule for later" but still received the same error.