Sharing some useful tricks for sending friend Request to unknown and mutual friends when you are blocked,Facebook mostly blocks from sending friend request for 30 days if you are blocked ever... hence this trick will help you to do that.. i guess you'll like it.
1. Get the person's email address first .
2. Visit Add Personal Contacts as Friends.
3. Here you can send friend request even if your are blocked by using their email address.
4. If you want to send friend request to lot's of friends here is an quick and easy way to do this.
5. Open up a new notepad file,paste all your friends email separated by comma (,)
6. Save the notepad file with the extension .vcf
7. This is your list of your contact files containing your friends email address.
8. Go to Add Personal Contacts as Friends click on the last option other tools there you can find upload contact file.
9. Browse your .vcf file and upload to the Facebook.
10. It will send friend request to your friend's by email and Facebook.