Can you check whether that particular model of computer supports ECC memory, and whether ECC memory is actually installed?
In most cases, ECC memory can detect and correct a single bit error, and detect and flag reliably all two bit errors, and detect most multi-bit errors. This error message means that an uncorrectable memory error has occurred (2 or more bits). That means your memory, or memory interface, or some connection is defective.
If your motherboard can not support ECC, or no ECC memory is installed, that error means that something is completely confused.
If ECC memory is installed, that error means that the memory has failed. In many cases, that is actually caused by contact problems. I would start by opening the computer, putting on a static safety strap and grounding yourself (*), and then one at a time pull all memory DIMMs and reseat them. In extreme cases, it may even help to clean any slight corrosion from the DIMM contacts with an eraser (the eraser end of a pencil works fine), just blow the dust from the eraser off. And if that doesn't help, then it was probably not a contact or corrosion problem, but you have had a memory DIMM or motherboard failure.
(* Footnote: Please do ground yourself with an anti-static armband. A few years ago we got a new computer that had a huge amount of memory installed, I think it was 768 GB, and I had to rearrange the DIMMs for best performance. This was at a time when such amount of memory were still considered extraordinary, and used very expensive DIMMs. I was not grounded, standing on a plastic ladder (the computer was rack-mounted high up), and I ended up destroying a DIMM with static electricity. That was a mistake that cost our group several thousand dollars. Don't make that mistake.)