Not an issue at all.Since you have applied by nextstep ,your are a fresher and faculties at ILP centre will help you.Once you join the company,you will get access to internal portal named Ultimatix,you can simply edit your name there and submit a valid proof to the corcerned person at ILP.Issue arises only name mismatches between your certificates.TCS is chill ,they give opportunity to correct our mistakes.All the best