Add this alternative spelling to your account. See "How do I add an alternative author name?" in https://help.researchgate.net/hc/en-us/articles/14292898263057 for instructions. However, this is only important for claiming authorship of papers. Independently of the spelling in the original paper, ResearchGate will always display your name with the main spelling you indicate in your account. But readers will see the alternative spelling when they open the full texts of your papers.