Doctors are stumped

(25m) I have been getting sick every other week for the past year and a half. I get fatigue, tingling in hands and feet, body aches, loss of appetite, and really bad brain fog. My health issues started when I got a bug bite on a camping trip about a year and a half ago. I was hospitalized for three days with an extremely low white blood cell count. Diagnosed with “arbo virus”. My doctor has done multiple labs and told me all my blood work looks good.

Lifestyle: gym 3x weekly, stretching, healthy food. Minimal alcohol/tobacco. 7+hrs of sleep. Occasional weed smoking

6’ 155lbs

I currently take magnesium, zinc, b complex, d3, turmeric, magnesium glycinate. daily

History: diagnosed with depression and anxiety. arbo virus 2023. I’ve had pneumonia in the past year. Covid multiple times since 2020

What could my problem be? What should I get checked next? Should I monitor my diet/ try elimination diet?