Answer:
Good Morning, Uncle
Hope you're doing well. I know you probably aren't too happy with my recent academic performance. It's just that I have a lot on my plate right now. I also can't seem to get the extra help I need. Due to all this, I've been stressing more than ever. I feel like that has had a negative impact on my studies as well. I'm working to fix these problems. Sorry to disappoint, hope to see you soon Uncle.
Sincerely, your favorite niece
Step-by-step explanation:
This is how I personally would have written the letter