Hi @Vaishnavi Gopalakrishnan ,
What is your SQL server version? Using select @@version to check this. Please read your Database Mail Log to find some useful information, and share us the information for analysis. Management->Database Mail->View Database Mail Log
Did you check the values of Database Mail Executable Minimum Lifetime as below screenshot? SSMS object> Management > Database Mail Configuration Wizard
Check if this thread could help you.
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