Task name shown as <...> in the output of EBPF program

I wrote a simple EBPF program which prints a message when the execve system call is invoked. I print the message using the bpf_trace_printk function. In the output, the task name for some processes is shown as `. For example, I ran the sh` command and the output corresponding to that is the following:

b'           -588130   ...21 512047.173196: bpf_trace_printk: Hello World!'

As you can see above, the task name is shown as ` instead of sh`. Why is that happening? How can I get the actual task name to be displayed?