How can I deactivate the reverse charge in zenfone 4 max?

[zapeexp]

ZF Model: ZE554KL
RAM: 2G
Firmware/APP Version: android 7.1.1
Frequency of Occurrence: every
Rooted: No
APP Name:

I'm trying to connect a piano via otg, the piano is great and is detected but the problem is that the cell phone starts to drain the battery by reverse charge and I want to prevent this from happening

[Christine_ASUS]

Hi mr.sureshvenkat
Thank you for your asking. Kindly provide the information below so that we could better assist you.
1. Model Name: Settings>System>About phone
Refer to the link below to check the model name by model no. in the link
https://www.asus.com/support/FAQ/1014441/
2. What kind on cable (USB, OTG..) are you using? Any other device connected? Do you need to press "power key" to activate the Reverse Charge? Or will any message pop out while you connect the cable to other device? Please provide me more details.

[thedimbel]

How to disable reverse charge in my phone

[Christine_ASUS]

Hi thedimbel 
Thank you for your asking. Kindly provide the information below so that we can better assist you.
1. The model names of the device in both side
Model Name: Settings>System>About phone
Refer to the link below to check the model name by model no. in the link
https://www.asus.com/support/FAQ/1014441/ 
2. Did you only use OTG cable or any other else?
3. Which function do you want to use for with OTG cable except for reverse charging?
4. Do the message pop out while you connect the OTG cable to other device? If you press "Cancel" of the pop-up message, what will it happen?