Foil wobble on water

[Cefirmeza]

Just tested an used ss hoverglide I got second hand and felt a bit wobble after take off. What causes this?
The kit looks and feels solid but there is some scratches and a small crack at the tip of the front wing. Is that it? Should it be sanded of maybe repaired so it feels smoother under feet?

Thanks

[tomtom]

Sometimes water is bumpy and wobbly and its is not apparent. Was it ok with other foil?