Error - There is no data to update.

This code is wrong. The element is a string. You must set all fields as array elements.

PHP Code:

    protected $allowedFields = ['einh_art_id,
    einh_etg,
    einh_lage,
    einh_qm,
    einh_zimmer,
    einh_kueche,
    einh_bad,
    einh_ebk,
    einh_dusche,
    einh_badewanne,
    einh_balkon,
    einh_terasse,
    einh_beschr']; 


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