Okay, I'm being serious here, no joking, been dealing with ear issues for a very long time (40'ish+ years), but my issues have been arrested for about ten years now. Typical surfer's ear, both sides.
I had tried about every plug on the market including, the ones already mentioned, and none of them gave me 100% confidence for various reasons, until I met an older, long time, surf guy whom I had respected from afar for years. We were talking after a good surf session and I asked him "what the hell is in your ears?" His answer~

Yep, Silly Putty, but it has to be the original one, flesh colored, in the red egg, imitations by different companies, or different colors made by the same company won't work, only this one does the job. The original, made by Crayola Corp.
It bonds with the skin like no other, but is also easy to remove by pressing the back of the ear. One eggs worth lasts me about one season, salt will eventually change the consistency making it softer, that's when you need to get a new egg. I get about 80 to 100 sessions per season.
Many of my friends have converted to Silly Putty and have been swearing by it ever since.
Hopefully they sell the stuff in your country.
Also, you have to keep your ear canals warm at all times to prevent surfer's ear from getting worse, if it's cold and windy, and I'm spending time out in it, like when I'm snow skiing, I wear foam plugs (the kind for loud sounds), they keep the cold wind out, and the canals warm.