I know. I can read. It doesn't matter whether it's turnover or profit. No one should stay at a company that's doing that much business with so few people without being paid more than that salary. Even if the company is making a loss then being paid £60k in a company with a £15m turnover is truly terrible. £15m is either a huge amount of work, in which case £60k isn't enough, or it's a reasonable amount of very expensive work, in which case £60k isn't enough.
The profitability of the company that you work for should have absolutely no impact on your salary if it's not making a profit. Do not accept less money for the value you generate just because the company can't sell it at a good price that makes a healthy profit. Your earning potential is not dictated by someone else's ability to sell.
If they are in low margin retail, or the "turnover" is really the turnover of their customers whose money they are handling - like for example an Amazon marketplace kind of thing, then 15m might be just a million of gross profit which is about about 70k per person. "Profit is sanity..."
The profitability of the company that you work for should have absolutely no impact on your salary if it's not making a profit. Do not accept less money for the value you generate just because the company can't sell it at a good price that makes a healthy profit. Your earning potential is not dictated by someone else's ability to sell.