call waiting in asus zenfone max pro m2 not working

[Aravind_s]

call waiting services in asus zenfone max pro m2 is not working for bsnl sim 

In the settings it shows the call waiting is already enabled. 

[Falcon_ASUS]

@Aravind_s
Unfortunately, your mobile phone model does not support the frequency band of this telecommunications operator.
We apologize for any inconvenience caused.

[Aravind_s]

Is the issue can be rectified in any software updates or the zenfone hardware doesn't support that frequency? that bsnl provides.

[Falcon_ASUS]

@Aravind_s 
For ZB630KL, there will no longer be any system updates and maintenance (including ZenUI Launcher). 
Sorry for any inconvenience it may be caused.