SoftBank Corp shares fell as much as eight percent early on Thursday before erasing the losses in volatile trading, following the telco’s 15 percent tumble on debut the previous day.

The unit of tech investment giant SoftBank Group Corp had raised 2.65 trillion yen (23.55 billion U.S. dollars) at 1,500 yen per share in Japan's biggest ever IPO. The slide has inflicted big losses on the retail investors who had mostly bought into the household name.

SoftBank Corp shares fell to a low of 1,176 yen before recovering to 1,309 yen. Parent SoftBank Group Corp's shares were down 1.7 percent.

The bumpy start for the shares have taken the shine off the listing of the telco, which has been hammered by bad news including a widespread network outage and government calls to cut carrier fees.

SoftBank Group founder and CEO Masayoshi Son hoped placing a value on the unit would help close the group's conglomerate discount, where its shares trade at a lower valuation than the value of the group's component parts, which include a stake in Alibaba, chip designer Arm Holdings and the $100 billion Vision Fund.

“The IPO seems to have no discernible impact on narrowing SoftBank's holdco discount,” said Arun George, an analyst who writes on independent research platform Smartkarma and calculates SoftBank Group's shares are trading at a 34-percent discount.

The benchmark index was down around one percent.