bug: add switch case to detect blank pointers in keeper

[alizahidraja]

Description

Added switch case to detect blank pointers in the keeper.

closes: #2268

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• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
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[alizahidraja]

Closing PR; Don't have access to the merging repo, will open a new one in the morning

[alizahidraja]

Continued here