@Viraj_s 

What is the device that connecting to the 2.4G network, what's the brand and model of the wireless adapter if it is a computer? Check the link speed when it is connected to the 2.4G network as follows:

https://www.tp-link.com/support/faq/2265/

That "Link Speed" is a theoretical value. Under real life circumstances one can usually get a data throughput of about 50-60% of that Link Speed if router and client device are in the same room.
 

Additionally, check that you have set the "Channel Width" in the router's 2.4 GHz wireless settings to "40MHz". You can also try to run the Wi-Fi analyzer to review the wireless channels, choose one that with less interference, then reboot the router and reconnect to the network to confirm.
 

@Viraj_s 

Are there other 2.4G devices available? Try to connect to the 2.4G network on another device, test if the issue persists, then we can locate if the issue is on the router, or it is the adapter.

You can also try to download and install the latest public driver for the WN725N on the computer, then reconnect to the network to confirm:

https://static.tp-link.com/2020/202006/20200601/00015960-RTLWlanU_WindowsDriver_1030.38.0712.2019_Drv_3.00.0032.L.zip

Note: Please remove or delete the other drivers you have installed for this WN725N on the computer first, then install the version.

How to install this driver manually on a Windows 10? Check this: https://www.tp-link.com/support/faq/920/.