@strangeseraph for a while the EA App would not register that I owned the Laundry Day SP. Everything worked fine on Origin, then I was forced to use EA app back in December. I was told to reach out to EA Help on Twitter and I'm not sure if they did much or anything at all (they didn't specify taking any actions), but after explaining my issue I opened up the Sims 4 and lo and behold Laundry Day was installed.
The pack still doesn't appear to be "In my collection" like other DLC. With all these issues it's hard to anticipate the future of this buggy app.
But perhaps EA Help on Twitter will be able to resolve your kit situation.