Lost all Battlefront II progression after moving from PS4 to PS5

Hi, I recently started playing Star Wars Battlefront II again on my PS5, but all my online progression is missing.

I originally played on PS4 using the physical disc and had years of progression, including high-level characters and unlocks.

I bought the digital version on PS5 because my console doesn't have a disc drive. I'm using the same PlayStation account, but everything is now level 0.

My PlayStation achievements go back to 2020, although my EA account says it was created in 2022.

EA Support told me my progression couldn't transfer because I originally played on disc, but I don't understand why that would affect online progression.

Could an EA community manager investigate whether this is an account-linking or server synchronisation issue? I'd really appreciate any help recovering my progress.