Hi,

Refer to these links. This gave an explanation of why certain fields it allows more than max length.

https://hi.service-now.com/kb_view.do?sysparm_article=KB0685779

https://www.servicenowguru.com/scripting/client-scripts-scripting/maximum-length-large-string-fields...

If you want to override this behavior, then you shall go with client scripts and restrict input after specified no. of chars.

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