Hey Wing Yan, I guess it's definitely a norm for being rejected than granted an offer...you should have so many programmes and opportunities ahead as there are still so many deadlines up and coming.

To improve / prepare better for your interviews, I would firstly suggest you to better present your career motivation ("why?") and career aspiration ("what do you see...?"). All of the experience and happenings you mentioned during your university years should be in perfect line with these 2 areas, which refers to "how" you pave your way for your career goal with a solid reason. You need to show you are a graduate with your own thoughts and not follow with peers' saying that some jobs are preferable than others so you choose this position. Obviously you would not say so but if you did not present / communicate well in Career Motivation and Aspiration, you might have left such an impression to interviewers.

Next, I think there are some basic techniques that you may wish to be aware of. For example, you should use different exp examples to support the main point / insights you wish to share with the interviewers, instead of purely using 1-2 similar exp or directly using your exp as your answers. Always draw some conclusions / learnings / implications from your exp! Another technique is that you should always answer the questions with a "project management" perspective, referring to sharing more of your business sense / the mature side of you.

For example, if you are suggesting your event organization exp to showcase one challenging time in your university years, you may wish to mention:

"in xxx months / weeks (period) you have collaborated with xxx members (number of teammates) to organize a xxxx (event) and attracted xxx participants and $xx of sponsorships (results) from corporates."

With the above, it may help in showing you are with Project Manager potential, or at least you can enhance the authenticity of the exp you have mentioned.

Not sure if it helps, but happy to see some more sharings from our fellow users! All the best!