The no-record result is almost certainly a timing issue, not a sign that something is wrong. When someone is freshly booked, jail databases can take anywhere from a few hours to a couple of days to update and become searchable. The news article confirming he is at Lehigh County Jail is reliable enough to go on in the meantime.
Mail is one of the most protected things in the jail and prison world. It is treated as a fundamental right for incarcerated people, and restrictions on incoming mail are extremely rare. You would only see that in high-security federal cases involving terrorism or organized crime. For a standard county jail hold, your friend can receive letters from day one, regardless of where he is in the process. He does not need to be convicted, sentenced, or permanently placed to get mail.
Go ahead and write to him now. Use InmateAid's letter service at inmateaid.com/letters to send your first letter. If you have already set up an account and created an inmate profile for him, log in and you will find him synced and ready to use across all the site's communication tools.
As for the search issue, try again in a day or two and his record should appear. If it still does not surface, call Lehigh County Jail directly and give them his full legal name. They can confirm his booking number and the correct mailing address format the facility requires.
Thank you for trying AMP!
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