You need to contact the developer of the theme because a feature of their theme is the conflict. Or more precisely something they are using in the theme. Many of the features in ACF depend on field keys and the developer of something that is meant for ACF should be aware of this and there should be something in it that allows you to set the collapse field for the acf repeater. You may need to look into this the “acf-field-group-composer”. Because you are using this you will need to play by their rules.
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