Is it normal for the visa issuance number to take this long to arrive?

Hello! I've been in Korea for almost 3 months now, and I need to start in March, but I haven't been able to book my flight yet. It's been almost 4 weeks since I've been waiting for my visa issuance number. Is this normal? Once I receive the number, I also need to send my passport. Has anyone had a similar experience? I'm worried about being late for my start date. 😢 I've heard that some people have received it faster, so I'm curious if it's just taking me this long. Is there anything I can do while waiting? Any advice would be appreciated! Thank you so much for your help.