In that case, could you please try to use the field key instead?
To get the field keys, kindly open the field group editor page and click the “Screen Options” menu. In this menu, please enable the “Field Keys” option for ACF PRO version or set the “Show Field Key” option to “yes” for the free version. I’ve attached a screenshot for your reference.
If that doesn’t work, could you please try to use the update_field() function?
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