I also fixed a couple of weeks ago, it's difficult at the moment because prices are the highest they've been since the start of the war in Ukraine, so longer term fixes at the moment could work out expensive to stay in and expensive to get out of if the situation in the Middle East stabilises.
Two years is a long time in energy prices, and for this reason, I went for 18 months this time, hedging my bets and will cover the next two winters, but it was also cheapest and didn't have as high a early get out fee as some of the others (think it's £50 per fuel).
However, I feel it's worth pointing out that your username suggests that you're a Utility Warehouse rep, so people should be aware of this, as in you get a commission for signing up other people to energy deals, which are usually poor value, because they might look OK priced, but you're compelled to take other services as part of the deal, and these can almost always be had for less elsewhere.
Apologies if this isn't true, in which case, you should be aware of the impression you're giving.