Duplicate "Date" in response header

I have a Webhook Contoller which returns "return response()->json();". In the header the Date is twice and the app, which calls the Webhook Controller, can not handle that :-( I use Laravel 8.83.13 and start it with "php -d memory_limit=-1 artisan serve --host 0.0.0.0". The Webhook Response looks like this:

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HTTP/1.1 200 OK Host: example.com:8000 Date: Fri, 21 Oct 2022 14:09:52 GMT Connection: close X-Powered-By: PHP/8.1.6 Cache-Control: no-cache, private Date: Fri, 21 Oct 2022 14:09:52 GMT Content-Type: application/json X-RateLimit-Limit: 60 X-RateLimit-Remaining: 59

[]

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I'am not able to find out, how to eliminate this duplicate Date. Does anyone can help me? Thanks in advance!