Telstra testing has revealed some Samsung mobile phone users may be unable to call triple-0 in an emergency with more than 70 models found not to be connecting correctly.

Telstra said the issue affected 11 older model Samsung Galaxy phones which users would need to replace with newer devices, and about 60 models that required system updates.

Telstra said affected customers would be notified via email or SMS.

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The telco said legal obligations meant customers who owned models that needed to be replaced would be blocked from its network if their phones were not replaced within 28 days of being notified.

"Under the gove

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