can some one help me with the rex command to extract the string included in first  from below pattern. For example: string to filter from below pattern is Proxy - Zscaler, Teams, Exchange and extract it under field "CI_Name"
[Proxy - Zscaler] [xxxxxxxr] USA US-22 Peer 2
[Teams] [xxxxxxx] Mexico Login - MX (proxy)
[Exchange] [xxxxx] Mexico Outlook Send Email - MX (proxy)