How to recover lost contacts from iPhone 6 after jailbreak?

I have an iPhone 6 may jailbreak it for a better experience and I'm not the exception. When I finished jailbreaking everything is OK except for my contacts taken by the iPhone 6. I can't find them. I usually synced my phone with iTunes. Now can I only restore lost iPhone 6 data after jailbreak?

Can't have a phone that doesn't exist. Think you meant 5.

I never had the issue of lost contacts after a jailbreak. In any case you should have backed up before doing it & from that you should be able to recover the contacts.

Go into settings>iCloud> and select contacts and make it green then it should restore phones contacts if not right away restart your phone.

Well, data losing from iPhone is a very common program, in fact, you can easily get back via some professional recovery tool even if after jailbreak, just like iPhone Data Recovery.
iPhone Data Recovery - a professional iPhone/iPad/iPod data recovery application which enables you to recover iPhone notes, images, videos, songs, text messages, contacts, notes and so on, as long as you have ever synced your personal data to iTunes on a computer. You are even able to preview the lost files before they are fully restored from the backup file of your iPhone/iPad. The software works without iTunes, simply download it to your computer and click to start scan. After that you'll see all your contents on your iPhone/iPad listed right in front of your eyes. The software works for iPhone 3G, 3GS, 4G, 4S, 5S,5C, 6, New iPad, iPad mini and more idevices.
You can read more from

Download the syncing app from here: www.apkforest.com

Try Jihosoft Mobile Recovery for iOS. This tool helped me recover lost contacts from iPhone 5 after jailbreak.

Firstly, you can rely on iCloud or iTunes to recovery iPhone contacts, after all, it is free.
1. Connect your iPhone with iTune on computer
2. Right-click or control-click on the iPhone icon under iDevice on iTunes
3. Select "Restore from Backup" from the given options
4. After it finishs, your contacts are back to your iPhone
Important Note: This works only if you have made a backup for your contacts on iTunes.
IF the iCloud or iTunes can't help to make a iPhone data recovery, you can turn to a third party tool.

Try FoneLab.

IPhone 6? I don't think so, it may be release this Sept. You can recover the lost iphone contacts via your itunes or icloud backup if you did that. Or you can only recover the lost data via some 3rd party tools.