i m working on Apex 23.1 (on premise), there are page items of type Number, i have a DA set value and it has PL/SQL Expression
TO_NUMBER(:P23_TOTAL_AMOUNT) - TO_NUMBER(:P23_PAID_AMOUNT)
on P23_PAID_AMOUNT, items to submit contains both above page items, and Affected Element contians P23_CHANGE_AMOUNT (this is Number type too)
all items contains Format mask: 999G999G999G999G999G999G990 and in Advance the Custom Attributes is : style="font-weight:bold;text-align:right;"
in Source the Data type of all above 3 columns are NUMBER.
when user enter some amount in P23_PAID_AMOUNT it is showing error:
Ajax call returned server error ORA-06502: PL/SQL: numeric or value error: character to number conversion error for Set Value
how it can be resolved as format mask and style is necessary here for the page items.

please help.
regards
note: i searched on google and found a solution as below, now it is not showing any error and calculating correctly:
TO_NUMBER(replace(:P533_TOTAL_AMOUNT,',','')) - TO_NUMBER(replace(:P533_PAID_AMOUNT,',',''))
seniors, please advise its ok or you have more better approach to replace above solution. regards