power automate – What format does the ‘Base Time’ field in the ‘Convert time zone’ action expect?

As shown in the screenshot below, the following timestamps format worked for me for onvertTimeZone(variables('TimestampYYYYMMdd'), 'Eastern Standard Time', 'UTC')

YYYY-MM-DD hh:mm:ss=> 2021-07-19 08:50:00 - Worked
MM/DD/YYYY hh:mm:ss => 07/19/2021 08:51:00 - Worked
YYYY-MM-DDThh:mm:ss.0000000Z => 2021-07-19T08:55:00.0000000Z - Worked

However, DD-MM-YYYY hh:mm:ss throws the error shown below

Unable to process template language expressions in action ‘Compose’ inputs at line ‘1’ and column ‘6070’: ‘In function ‘convertTimeZone’, the value provided for date time string ’19/07/2021 09:51:00′ was not valid. The datetime string must match ISO 8601 format.’

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