Hi Vidmantas
At this time, architect does not support regex in inbound email flows, there is an idea on the Genesys Cloud Product Ideas lab: Architect - Regular Expression support for Architect inbound email flows I would recommend voting on the idea and adding your use case.
Hopefully someone else in the community can help with alternatives to getting the information required out of the email.
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Sam Jillard
Online Community Manager/Moderator
Genesys - Employees
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