String was not recognized as a valid DateTime - Why this error is coming suddenly?

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5

set a breakpoint before the type into
debug and get paused
use the immediate panel and inspect the CurrentRow(“Posting Date”).ToString Value

Understanding the 6 Debugging Panels of UiPath in the easiest way possible! - News / Tutorials - UiPath Community Forum

Also you can directly prototype the possible corrective statements within immediate panel

For analysis statements to find all invalid, out for expected format dates have a look here:
:ambulance: :sos: [FirstAid] Datatable: Debug & Analysis invalid DateTime Strings / String to DateTime Parsing Issues - News / Tutorials - UiPath Community Forum