Myntra Invalid Number At Checkout, Customer Service Unreachable

I tried to use this Myntra gift I got but the website just wouldn't take it, kept putting in the number at checkout, but it kept saying it was invalid, which is impossible as it hasn’t been a year yet, triple-checked the number, definitely wasn't me messing up. Tried calling Myntra customer service to get it sorted, but after being on hold for what felt like hours, I still couldn't get ahold of anyone. hoping maybe you can help troubleshoot this tech gremlin for me? Wouldn't want this gift card to go to waste! The number on the card is 1*5*-5678-9**2-34*6 (just in case), and it would be amazing if someone could reach out and help me figure this out.