Question

I tried creating lookalike audience from my existing leads of interesting clients but got error of audience not created.
What could be the reason? I tried two times, list size is around 400 people of same country.

Answer 1

If you're getting an error when trying to create a Lookalike Audience from your existing lead list (~400 users, same country), the issue is likely related to one or more of the following factors:

1. Source Audience Is Too Small or Poorly Matched

Meta requires at least 100 matched users from a single country to create a Lookalike.

With just 400 leads, your upload must:

• Match at least 100 users to Facebook profiles based on email/phone/etc.

• Be from the same country (which you’ve done right).

If only 50–80 match, it won’t work.

What to do:

• Use email + phone together (if available) to improve match rate.

• Format your CSV with headers like email, phone, first name, last name.

• Double-check country is spelled correctly and uniform in the file.

2. File Format or Mapping Errors During Upload

If fields are not mapped properly (email as "other", or incorrect formatting), Meta might not be able to build the seed audience.

Checklist:

• Use a .CSV or .TXT file

• Column headers should be:

  email phone first_name last_name city country 

• Make sure:

  • No blank rows

  • No special characters or emojis

  • Phone numbers include country code (+91, +1 etc.)

3. Custom Audience Is Not Yet Ready or Approved

Sometimes, Meta needs time to process and match the custom audience. If you try to create a Lookalike before it’s processed, it can fail.

Wait at least 30–60 minutes after uploading the list before creating a Lookalike.

4. Audience Violates Policy (Unverified Source)

If your uploaded list is not properly sourced (e.g., purchased or scraped), Meta may block it.

Make sure you’re uploading a first-party list collected with consent.

5. Duplicate Upload Errors

If you tried to re-upload the same list with slightly different names, Meta may glitch or reject the audience.

Try:

• Deleting old failed audiences

• Renaming your source audience

• Uploading again from scratch

Pro Tip: Test Match Rate Before Building Lookalike

Once you upload a custom audience:

• Go to Audiences → Click the uploaded list

• Check for status:

  • Ready or Not enough matched users

If it says “Below minimum size for Lookalike,” you’ve confirmed the issue.

What to Do Next

If the list is too small or match rate is low:

1. Try expanding it to 800–1000 leads

2. Include email + phone + name for better matching

3. Use Engaged Facebook/Instagram users as an alternate source:

   • Create a custom audience of:

     • Engaged users in last 90 days

     • Video viewers or lead form openers

   • Then create Lookalike from that

Answer 2

The most likely reason for the "audience not created" error with a 400-person list is that your source Custom Audience is too small for a Lookalike.

While Meta technically allows a minimum of 100 people from a single country, they strongly recommend at least 1,000 to 5,000 people for a Lookalike Audience to be effective and for their system to properly identify patterns. With only 400, the data might be too sparse for their algorithm to build a robust "lookalike" profile.