Battery specs and Coding

[JulzTDI]

Hi all wonder if anyone can share some information. I drive a 2019 Audi A3 35tfsi stronic with 70000kms. I recently purchased. However previous owner changed the battery to a normal acid battery without coding. Not knowing after a few drives car started with electronic issues, hard changes engine idles rough and a fault saying battery charge low, vehicle will charge while driving. Eventually battery ran out and car didn't start. The battery was then replaced and apparently coded with a Dixon Agm battery 668 80ah. However when i checked the coding it was coded saying EFB tech. Under impression it was not coded correctly after driving started getting the same error above battery low. So ended up coding the car via vcds. But the battery lost surface charge. Took the battery to a battery centre and had it charged fully. To also note that when the battery was changed the car ran perfectly for a week no issues no errors, after a week Electronics feel funky. Should i recode? Or could this battery not be compatible with the car? Start stop functions sometimes work gear changes feels harsh, engine feels on limp. However no fault of battery being low any longer. Any assist will be appreciated. No faults on vcds. After battery been charged. Could be that i might have the coding incorrect? Do i reset the bms? So far i had alternator tested, Thanks in advance. Any further info needed let me know.