I have had the same issue, turns out the checkout was deleting the file before it had the time to analyse it. You should double check the location of the file and check what's been deleted in the checkout. Although this might not resolve your issue. What I have done to resolve it is that i have uploaded the lcov file as an artefact if the pipeline during my test, then, i downloaded it at the root of my project during the Sonar Cloud stage and double checked its location multiple times before it worked.