Can't purchase Sims 4: Lovestruck – cart won't update

Hello,

I’m experiencing an issue trying to purchase The Sims 4: Lovestruck Expansion Pack during the current sale.
Every time I try to add the pack to my cart through the EA App or the EA website, I get the following error:
"We're having trouble updating your cart."
This only happens with Lovestruck. I’ve already successfully purchased another DLC from the sale using the same account, region, and payment method, so the issue is not related to my location or payment.

I’ve already tried:
Restarting the EA App
Clearing the cache using App Recovery
Switching to English language
Logging in through a browser (Chrome)
Re-adding my payment method
None of these steps resolved the issue.

Please help me complete the purchase or advise what else I can do.
Thanks in advance,
Roni.