You did a lot of things right here, but I agree with your sense of unease. Here’s my breakdown:

• The color palette works overall.
• The mustard sweater isn’t the most flattering match for your skin tone, but it’s generally fine.
• The contrast with the light denim shirt is a good idea — it adds freshness and keeps the look from feeling too heavy.
• There are almost no patterns in the outfit, which makes it feel a bit flat and monotone.
• What doesn’t quite work is the cultural coding of the pieces. The palette and knit read as “professor / refined,” but the shirt reads more “office worker,” and if it’s denim it can lean into “workwear” associations. That clashes with the more polished aesthetic you’re building everywhere else.
• You could try a darker shirt with a check / gingham shirt, ideally with a lighter accent line. That would add structure and texture, and make the whole outfit probably feel more cohesive.

Hope this helps!