form autocomplete a field with the value of another field

in a form I have 5 required fields, two of them are date type, doing tests I filled in 4 required and tried to save the record, it shows me the message that I need to fill in a required field (that's fine) but when I click on okay to the message and then return to the form, it autocompletes the missing field with the value of another date type field

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Maria Del Carmen Ortiz Garcia
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