Good morning, GHOSTLY, welcome to the Forums to you and Spring!
Some parrots take to pellets straight away, some would almost rather starve themselves to death than convert over. I have had mixed results with two cockatiels. Many years ago when pellets were not so commonly used, my then cockatiel Kang resisted ALL ATTEMPTS and would definitely rather have starved than eat them. Of course it might have been my fault for not presenting them in the correct manner, but she never did manage to convert.
A later arrival to the flock, Twinkle, was
almost as stubborn, and it took several attempts to win her over. What finally worked for her was that I crushed up the pellets into a powder using a mortar and pestle, and sprinkled that all over her seeds. This made it impossible for her to just sift through and eat only what she wanted, without getting a proportion of the crushed up pellets in every bite. It also got her accustomed to the different taste and smell. Et voila!! She was converted over to pellets in just a matter of days when she had previously fought every other attempt!
Other factors may be that Spring simply is not keen on the taste or smell of that particular brand of pellet, so it may also take experimentation with several brands before settling on one that he likes. But it's worth being persistent so don't give up!
Oh and don't forget to post some pictures, we love baby photos around here
I wish you the best of luck!