It's normal for natural gas prices to increase or decrease sharply. Among others, the demand for it is dependent on weather and subject to seasonality. This is very intuitive: if it's colder, there is an increased demand for heat (fuels), and natural gas is that fuel.
The spike in natural gas prices in January 2026 can be explained by the severe cold/snow storms and their effects on supply, demand and storage across the United States and Europe.
But you don't need to know any of that. All you have to do is open a historical price chart for natural gas.
From 2020 to 2022, natural gas prices increased almost ≈x6.5 in price. Then, from 2022 to 2024, the prices fell by ≈84%, bottoming just ≈6% above the 2020 lows.
Thus, any sources proclaiming that "it is not normal" for NATGas to increase 70% in roughly two weeks, implying that it's a signal of a major distress in the system, are unlikely to be a reliable source on this topic.