We will soon link the public knowledge base which can be referred by help seekers to resolve if they face any issue, which is also summarised as below.
After all the analysis we found that there is no discrepancy on the Jira Service Management side rather, user will have to ensure to try some of the below steps to resolve the captcha error.

Hi, 
We're working on a public knowledge base article to explain the reasons and possible fixes for reCAPTCHA verification failure. Here's summarising the content of that article. 

 
reCAPTCHA verification can fail due to a number of reasons:

1. Suspicious behavior: If the system detects activity that resembles automated software rather than genuine human interaction, it may fail the captcha test.

1. Human error: Sometimes users make mistakes when completing the captcha, such as misreading distorted text or clicking the wrong boxes.

1. Unusual traffic patterns: Captcha systems analyze browsing behaviour to distinguish between human users and bots. Using a VPN or other means to alter your traffic patterns might trigger suspicion and lead to captcha failures.

1. Flagged IPs: Certain IP addresses, especially those associated with VPN servers or known for spam or malicious activity, may trigger captcha failures.

To resolve reCAPTCHA verification failures, you can take any of the following steps:

1. Detect and remove Malware: Malicious software on your device or network could trigger suspicious behavior and lead to captcha failures. You can also run antivirus scans to detect and remove any malware.

1. Try an alternate browser: Sometimes, issues with captcha verification may be specific to a particular web browser. Switching to a different browser can help bypass these problems.

1. Contact network administrators: If the issue persists, you can try reaching out to your network administrators or IT team. There might be network-level configurations or issues causing the captcha failures.

1. Uninstall VPNs: If you are using VPNs, consider uninstalling them, as VPN servers may be flagged by captcha systems due to their association with suspicious activity.

1. Contact internet provider: You can also contact your internet service provider for assistance. The provider may be able to address issues related to flagged IPs or unusual traffic patterns.

Hope the problem can be resolved by trying one of these fixes. 

Hi, this is becoming a big problem for our team. We need to validate an implementation and we're not capable of do that because the client needs to access to the instance, and the captcha is not allowing them.
We need a solution as soon as possible please!

This is an issue for us as well.

https://getsupport.atlassian.com/browse/JST-934639