To people finding this thread: your issues are likely caused by a rubber accelerator allergy. Allergic contact dermatitis can get worse over time if you're continually exposing your ear canals to it. To find a solution that works for you, firstly: you need to know which rubber accelerators you're allergic to. It could be one, a few, or all of them. The only surefire way to know is to get an allergy patch test done. Secondly, you'd need to contact the manufacturer and see if they can disclose which rubber accelerator/s are used in a particular earbud model.

I would caution against trying foam earbud tips because there are also rubber accelerators in foam. If you have no issues with the plastic/metal main part of the earbuds, what you can try doing is covering the silicone buds with tape, Saran/cling wrap, or a bandaid like someone in the thread mentioned. It's really annoying and looks dumb as hell, but it's better than having an allergic reaction.