Personal Injury Claim Help please

[JPC]

Im looking for some help regarding my personal injury claim. Long and short is I had a serious accident at work 3.5 years ago. I was a tradesman and I now no longer can do that job. This has been confirmed within my medical report that my accident lawyers obtained. I was self employed by Company B who were subcontracting to company A. Company A chose to put me onto light duties as a storeman for 18 months rather than be a tradesman as that was no longer possible due to my injury. The project ended and I was dismissed. Company A have admitted full 100% liability. Now for some reason my accident lawyer is saying that as company B continued to pay my wages(hourly paid) as a tradesman I can not then claim for loss of future earnings. For the 18 months I was paid as a tradesman even though I was actually being a storeman to which I found out later was to stop Company A from having to report to HSE. To put it into perspective pre accident I was earning £70,000, post injury is £26,000 per annum. Im failing to see why my accident lawyer is saying they cant claim for loss of future earnings. Im only 36 I have at least 31 years left of my working life. Any help, advice or guidance would be greatly appreciated.