iPhone 12 Pro Max continues to ring for 5 seconds after recipient answers call

I am experiencing an issue with my iPhone 12 Pro Max running iOS 18.4 When I make a call using the physical SIM card, the recipient answers, but my device continues to ring for an additional 5 seconds before I can hear their voice.

I have attempted the following troubleshooting steps without success:

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• Restarted the device. 
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• Updated to the latest iOS version.
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• Reset network settings. 
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• Tested with a different SIM card.
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• Disabled 4G/5G.
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Despite these efforts, the problem persists. I have also noticed similar reports from other users in the Apple Support Community, such as this thread:

Could you please assist me in resolving this issue?

[Re-Titled by Moderator]