Issue check box (multiple choice) custom form email notification

Hello,

The custom form email notification is working fine except for the “Drop down” with the multiple selection enabled.
When receiving the email notification, the data is “Array” while on other field like “Text Area” the data is exactly what has been written :

How many km do you live from the destination (range) ?
Array

Other question, for the text area with big dimension enabled, how can we output the break line in the notification email. For now, in the notification mail, the message is displayed on one line while entered in the form with multiple line breaks :

Hello I am a Test, I need to book this time slot. This line should be under the other one. Is it possible to take our dog in your hotel ? Thank you, Have a nice day, Test

Thank you for your advices.