Array to string conversion error when using implode

You have an array of arrays... Try this:

$error_c = implode(',', $matches[0]);

php arrays string implode

$error_c = implode(',', $matches[0]);echo $error_c;

because your array contains arrays inside

php arrays string implode

You may use array_values() for array of arrays

e.g. implode (",", array_values($array))

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