How urgent is it for you to have access to that money over the next few years?
Look, if you're really not going to touch it, 3-4% is still better than letting it sit and rot in your checking account where you barely make anything. The thing is, those interest payments barely cover inflation - depending on how things go, you could still be losing purchasing power anyway. What I did was split it up: part in a fixed deposit so I can sleep at night, and I put another chunk into safer investment funds but with the potential to earn a bit more, though obviously there's volatility and fees you've gotta look at carefully.
If your timeline is really years out and you don't need the money, it's worth looking into what's out there beyond just a fixed deposit - index funds, bonds, fixed-income funds. But that's all down to how much risk you're willing to take on. A fixed deposit is the most boring thing but also the safest.