How do I reconcile 2 companies on one bank statement?

PSCSS

We have recently restructured our business and in doing so have a period where 2 different companies are using the same bank account. I am now trying to reconcile and finalise the old company but by entering the ending balance of the bank statement it will never balance out - the same with the new company - is there a way to allocate a part of the bank statement to either company?