function setTotalSharesOfAccountInternal(address account) internal pausable {
  require(
    isVcaRegistered[account] == false || hasRole(MIGRATOR_ROLE, msg.sender),
    "STAKING: Account already registered."
  );

  uint256 totalShares;
  uint256[] storage sessionsOfAccount = sessionsOf[account];

  for (uint256 i = 0; i < sessionsOfAccount.length; i++) {
    if (sessionDataOf[account][sessionsOfAccount[i]].withdrawn) continue;

    totalShares = totalShares.add(
      sessionDataOf[account][sessionsOfAccount[i]].shares
    );
  }

  uint256[] memory v1SessionsOfAccount = stakingV1.sessionsOf_(account);

  for (uint256 i = 0; i < v1SessionsOfAccount.length; i++) {
    if (sessionDataOf[account][v1SessionsOfAccount[i]].shares != 0) continue;

    if (v1SessionsOfAccount[i] > lastSessionIdV1) continue;

    (
      uint256 amount,
      uint256 start,
      uint256 end,
      uint256 shares,
      uint256 firstPayout
    ) = stakingV1.sessionDataOf(account, v1SessionsOfAccount[i]);

    (amount);
    (start);
    (end);
    (firstPayout);

    if (shares == 0) continue;

    totalShares = totalShares.add(shares);
  }

  isVcaRegistered[account] = true;

  if (totalShares != 0) {
    totalSharesOf[account] = totalShares;
    totalVcaRegisteredShares = totalVcaRegisteredShares.add(totalShares);

    for (uint256 i = 0; i < divTokens.length(); i++) {
      deductBalances[account][divTokens.at(i)] = totalShares.mul(
        tokenPricePerShare[divTokens.at(i)]
      );
    }
  }

  emit AccountRegistered(account, totalShares);
}