Please rename meta key "fpd_data" to "_fpd_data" with "_" prefix which mark it as "hide" meta.

Many plugins try to show it as variation meta.

seems it is not all the files changed correctly

i.e.:

/woo/class-wc-product.php

and

/woo/class-wc-cart.php

they both operate only with "fpd_data" meta key (era before 3.4.9)