NotifyMe app on mobile phone often fails with "character string buffer too small" error

Often in the NotifyMe mobile app, the user is presented with an empty notification screen, when we know for sure there are requisitions and/or purchase orders that are waiting to be authorized by the user.

When we check the touch apps log file, we see the following error:

Error when synchronizing entity FndStreamExtension: Failed executing query (ORA-06502: PL/SQL: numeric or value error: character string buffer too small
ORA-06512: at "IFSAPP.PUR_REQ_NOTIFICATION_API", line 599
ORA-06512: at "IFSAPP.PUR_REQ_NOTIFICATION_API", line 599
ORA-06512: at "IFSAPP.PUR_REQ_NOTIFICATION_API", line 633
ORA-06512: at line 1
ORA-06512: at "IFSAPP.NOTIFY_ME_UTILS_API", line 401
ORA-06512: at "IFSAPP.NOTIFY_ME_UTILS_API", line 406
ORA-06512: at "IFSAPP.NOTIFY_ME_UTILS_API", line 347
ORA-06512: at "IFSAPP.NOTIFY_ME_UTILS_API", line 358)

When I check the API on the lines indicated, it seems to fail when assigning a value to the "detail_line_" variable, which is defined as varchar(2000).

 FOR line_rec_ IN purchase_order_details(notification_rec_.order_no) LOOP
         detail_line_ :=
            line_rec_.line_no || ',' ||
            Mark_Down_Utils_API.Add_Hyphenated_Strings(line_rec_.part_no, line_rec_.description) ||','||
            NVL(line_rec_.vendor_name, ' ') || ','||
            Mark_Down_Utils_API.Add_Hyphenated_Strings(line_rec_.quantity, line_rec_.unit) || ','||
            line_rec_.planned_delivery_date || ','||
            notification_rec_.currency_code || ' ' || line_rec_.total_amount || ','||
            notification_rec_.currency_code || ' ' || line_rec_.total_gross_amount || ','||
            notification_rec_.contract;

I suspect the compound value it is trying to assign to the variable is more than 2000 characters, which results in the ORA-06502 error.

Is it possible to increase the character limit on the detail_line_ variable, maybe to 4000?

For both PUR_REQ_NOTIFICATION_API and .PUR_ORD_NOTIFICATION_API, so that the NotifyMe app can work with bigger line item descriptions coming from the purchase orders and requisitions?  A limit of 2000 characters for the combination of line number + item description + vendor name + quantity + unit + delivery date + currency cod + total amount + gross amount + contract seems too small.