The Bank of Tokyo-Mitsubishi UFJ said Monday its customers using cash cards of the former Bank of Tokyo-Mitsubishi are currently unable to withdraw cash via automated teller machines at Seven Bank.

The trouble occurred as BTMU introduced a new computer system, which integrated the computer systems of its founder banks—the Bank of Tokyo-Mitsubishi and UFJ Bank—at some of its branches the same day.

BTMU, the core bank of Mitsubishi UFJ Financial Group Inc, said the malfunction prevented a total of 7,750 transactions from being executed between 7 a.m. and 9 a.m. and that it was trying to fix the glitch as quickly as possible.

The bank was established in January 2006 through the merger of the two founder banks.

As the founder banks’ computer systems have yet to be fully integrated, customers with Bank of Tokyo-Mitsubishi cash cards are unable to access the full range of services through ATMs of the former UFJ Bank and vice versa.

On Monday, BTMU introduced the new system at some 250 branches, which used to be those of the Bank of Tokyo-Mitsubishi.

It plans to introduce the integrated system at the remaining 420 branches, which were once UFJ Bank outlets, in stages from July through December.