Any recommendation to make the tan lines disappear fast? I get it from swimming. In just one day, I have tan lines now omg how do I wear drop shoulder next time? SPF doesn't work? Need to keep on reapplying when swimming?

SPF for swimming recommendation?

Whitening cream recommendation for tan lines?

Home remedies recommendation for tan lines?

Sunscreen doesnt stop u from getting tanned, it just doesnt let u sunburn. Tan is due to melanocytes reaction to sun ray to produce pigment.

SPF = Sun Protection Factor
It's definitely recommended to use daily. For daily use, SPF 30 is enough. You're still young, so you may not be familiar with dark circles or pigmentation issues yet.

As for your current problem, perhaps licorice extract could help. Licorice has been proven effective at dispersing melanin. You probably can read more about it on your own first.

Time heals tan ...btw tan lines are sexy

Aloe vera gel is good in reducing the redness and irritation from sunburn, but there's really nothing you can do for the tan line except waiting to let it pass. Opt for swimwear with sleeves in the day or have swimming session at evening/night.