Common reasons for low match rate.
Your apps may experience less demand from Google while they evaluate your traffic quality. This can occur for up to one week after a new app or ad until is created.
If you still have low match rate after one week, use the following guide to understand common reasons for low match rate.
* Account changes
* Ad serving changes
* Usage changes
I unable to put link here because this is a new account.
Search on google.
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