title: Argument of type 'string' is not assignable to parameter of type '`${string}` | `${string}.${string}` | `${string}.${number}`'
body: <p>I've migrated <code>react-hook-forms</code> from v.6 to v.7.</p>
  <p>After changing the <code>register</code> method, as pointed out in the <a href="https://react-hook-form.com/migrate-v6-to-v7/" rel="noreferrer">migration guide</a>, the following error occurs:</p>
  <blockquote>
  <p>Argument of type 'string' is not assignable to parameter of type '<code>${string}</code> | <code>${string}.${string}</code> | <code>${string}.${number}</code>'.  TS2345</p>
  </blockquote>
  <p>Register expects a string name, which I provide correctly with a param which for sure is a string, but anyhow it doesn't accept my parameter if I don't pass exactly string.</p>
  <p>Anyone with a similar issue or any idea is highly appreciated. Thanks in advance!</p>