Hi @aarzoo2001
Sorry i was mistaken at first, we do not support the merging of coverage files coming from multiple languages (such as your case)
My best solution for you would be to split analyses in 2 separates SonarCloud projects (One analysis analyzing the dotnet code with coverage for SC project 1, and the other one for js files with their coverage as well for SC project 2 for example) to ensure the best results.
HTH,
Mickaël