Thank you for your post and I apologize for the delayed response!
I understand that you have questions regarding the Microsoft Sentinel free trial and whether or not a CSP customer is eligible for this, and to hopefully help point you in the right direction or resolve your issue, I'll share my findings below.
Findings:
I'm not too familiar with CSP's and their subscription plans, based off my understanding when it comes to the Microsoft Sentinel free trial, and as mentioned by Tushar Kumar - you should be able to try Microsoft Sentinel free for the first 31 days (subject to the limits stated).
When it comes to website you shared asking for credit card details, this is possibly related to the user trying to start an Azure free account and the credit card details being used for identity verification purposes.
If you have any other questions, please let me know. I'd also recommend reaching out to your CSP directly if you're having any issues with the Microsoft Sentinel free trial, or you can chat with our sales team directly from the pricing page.
Additional Links:
I hope this helps!
Thank you for your time and patience throughout this issue.
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