Maybe it was an accident, or maybe you didn't think you needed to talk to this person again, but you deleted a phone number or contact from your iPhone, and now you need the number again! Let's go through some ways you can try to find that phone number.
If you called them, or received a call from them in the past, you can open the "Phone" app and select "Recents" at the bottom. Try scrolling down through the recents, and see if your last phone call with them is in the history still. If so, the call should appear listed by phone number.
If you texted them, or they sent a text to you and can remember some words of note from the text conversation, you can try searching for that notable text in your iPhone search. This search uses data that isn't purged very often (the spotlight cache), so the message may show up even if the text messages were deleted long ago. The search result should show up listed by number since the contact was deleted (definitely let us know in the comments if you experience otherwise). Here's an example of me searching for the automated number that the Google two-factor authentication texts come from, after having deleted all of those texts from my iPhone.
If the two approaches above don't work, and if you ever sent them at least one text, we can dig into a deeper history of phone numbers used from your iPhone. Our Decipher Backup Browser tool has a section called "Recently Used Contacts". We can use that to look for old numbers (and dates/times you sent a message out to them) to help us find the number. The recents list goes back in time quite a while — my current backup made in 2017 has some entries from 2013 and 2014! Decipher Backup Browser will show you the number/email address even if there's no entry in your contacts.
You may need to make a backup in iTunes of your iPhone if you don't have one already, but if you do have one, you may want to look at your old backup before making a new one!
- Run Decipher Backup Browser.
- Select your iPhone backup in the left column.
- Select "Recently Used Contacts" in the middle column.
- Scroll down through the list of contacts you texted and emailed, which should progress back in time. If you find a number that you think might be it, used the dates of communication to help verify your guess.
I was just thinking I should change the name of the Recently Used Contacts in Decipher Backup Browser, since it is neither limited to only recent information nor is it limited to Contacts! If you have a suggestion for what I should rename this section, please leave a comment!