Zenfone 5 draining superfast after service and battery replacement

[dianape]

Please tell us some basic information before asking for help:
Model Name: Zenfone 5z
Firmware Version: android 10. I don't have any field as Firmware version in Model & Hardware.
Rooted or not: no
Frequency of Occurrence: everyday
APP Name & APP Version (If your issue relates to the app):
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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My Asus Zenfone 5z was dead a few days ago. After contacting Asus Authorised Service Centre, they did servicing and replaced the battery. Now, my phone discharges in 12 hours even on Airplane mode and no apps running. Also, the phone takes about 4 to 5 hours to charge fully on Airplane mode. I even did factory reset and tried all battery optimisation options. What's worse is the battery app doesn't even indicate which app consumed all the power. All I see is
Screen: 30 mins 6%
Phone Idle 11hrs 30 mins 2%
Android System 2%
Is the issue with the replaced battery? How can I check whether the replaced batter is genuine?

[fussion_ASUS]

Hi, please check your inbox for the private message I've sent you, since the further information that we need involves your personal information. Thank you.

[dianape]

Hi,
I contacted the service center and they did a battery replacement again on 23rd July. Now after full charging, the phone discharges in about 7 hours! Worse than the earlier replaced battery.
Asus support executive alongwith service centre person called and promised to provide repair costs estimates. Now, more than 24 hours later I don't see any mail. I expect service centre to find fault and provide quote instead of just saying motherboard components might need to be replaced 😞

[dianape]

No mail from Service Center or Asus regarding repairs. After repair and replacing battery twice, I'm left with a dead phone. The last battery replaced doesn't even charge. Very pathetic service.

[ASUS_Bot]

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