For Airtel,

1. Call forwarding Unconditional - **21*<10 digit number>#
2. Call forwarding - no answer- **61*<10 digit number>*[05-30,step=5]#
3. Call forwarding - busy - **67*<10 digit number>#
4. Call forwarding - not reachable-**62*<10 digit number>#

To cancel , replace * with #.
Source

Get second hand Apple iPhone 6s (Rose Gold, 32 GB) @ 12k

M4A: M4A tends to have substantially better quality than MP3 and OGG. An M4A file created with the lossless ALAC codec has the quality of an original lossless studio recording. ... Even the M4A created with the AAC codec (which is lossy) has better quality than MP3 and OGG.
MP3 < OGG < M4A
#file_formats

right click and run as admin

Tasker Profile v2