I assume the messages are iMessages. If your iPad is sharing the same Apple ID that would be why they are going there or if messages are being sent to your Apple ID but you don't have it enabled on your iPhone to receive messages sent to your Apple ID but it is on your iPad that would be why.
Ensuring you receive your messages correctly is important zegs. Let’s ensure your messages are being sent to the correct device. When did this start? Are messages that are being sent to your iPad instead of your phone iMessages only? Are you using the stock messaging apps on your phone or a third party app?
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