Usually, sticky residue on plants is caused by honeydew - the sugary excretions of pests like aphids and scale. Scale can be particularly hard to spot, but if you don't see any, feel free to send us pictures of the plant's stems/foliage (upper and lower surfaces) so we can look for issues. Some plants naturally produce exudates (secretions) which can be sticky, though it's not likely a Goldfish plant is doing so. Is this plant growing next to or underneath another, taller houseplant or one which is in a basket hanging above it? Perhaps the honeydew is falling from another source.

Miri

Yes, we agree.  The scale was well camouflaged. Easiest solution is to say good-bye.

Here's our page on houseplants and scale: https://extension.umd.edu/hgic/topics/scale-insects-indoor-plants

Ellen