19 and Need Advice with TSP

My dad told me to stop investing in the market and put all of my money into my TSP. I think that’s probably the worst advice I’ve ever gotten. I’m only 19, so that doesn’t seem ideal. I already contribute 5% for the full match, and I’ve been thinking about increasing it to 10%.

All of my funds are in L 2065, and he’s telling me to keep it that way because it’s showing a 22.60% return. However, someone else told me I should consider switching to the C Fund instead.

What are your thoughts? Do you think he’s right?