Hey @Veelahs,
Your game progress is currently saved to the EA account where it was first earned, which is why that appears to have been largely lost after linking your PSN account to a different EA account.
I'm afraid the only way to restore this would be to re-link your PSN back to the original EA account where that progress was made. If you're unable to do this on your end or run into any issues, feel free to ...
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