SuiteCRM 8.2.4 case subject variable empty


I have recently upgrade to SuiteCRM version 8.2.4 installed on Ubuntu (18.04) with MYSQL 5.7 and php 8.0.

I have managed to create case from emails but the email subject line always remains empty , it appears as ‘no subject)’ .

I would really appreciate it if someone can help me understand why this could be happening and a fix for the issue?