You wouldn't generally say "for" after "request" like that. I ask for deletion of my account = grammatically ok but not totally natural like a native speaker I request deletion of my account = grammatically ok but not totally natural like a native speaker I request for deletion of my account = awkward grammar, even less natural I request for my account to be deleted = more natural than the options you provided, but still lost between tons I humbly request for my account to be deleted = smooth and hyper humble tone, perfectly natural and efficient Please delete my account immediately = smooth and hyper assertive, minimalist tone for maximum understanding and acknowledgement potential

I agree with Dan. Here are some native-like alternatives: “Please delete my account.” (polite and direct) “I would like to request that my account be deleted.” (formal) “Could you please delete my account?” (polite and natural)