How to translate donate form labels with loco translate

Hi,
We installed charitable plugin, all things are showing fine.
I want to translate English to french for donation form labels.
These texts I couldn’t translate to french language with polylang and loco translator.
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” First name, Last name, Email, Address, Address 2, City, State, Postcode, Country, Phone Number ”
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I have used for multi translate polylang.
The custom translation used for Loco Translate plugins.
But translate not working for the donation form.
How can I do translate to french(Donation form labels)?
Have any documentation for that?
I hope ur best.
Thank you.

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