""ERROR_WHILE_CONVERTING_VALUE_TO_STRING" error seen in witness logs

Following error is printed during son payout

2022-02-19T17:00:00.500 th_a:invoke handle_block         handle_block ] Got block: #47507403 time: 2022-02-19T17:00:00 latency: 500 ms from: eifos-witness  irreversible: 47507395 (-8)                 application.cpp:459
2022-02-19T17:00:00.501 th_a:invoke handle_block process_dividend_ass ] In process_dividend_assets time 2022-02-19T17:00:00                     db_maint.cpp:1739
2022-02-19T17:00:00.673 th_a:invoke handle_block schedule_pending_div ] payout_asset_type: 1.3.0 current_balance: 1 previous_balance: 0                         db_maint.cpp:1494
2022-02-19T17:00:00.673 th_a:invoke handle_block schedule_pending_div ] total_fee_per_asset_in_payout_asset: 0 dividend_data.options: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"]                        db_maint.cpp:1534
2022-02-19T17:00:00.680 th_a:invoke handle_block schedule_pending_div ] payout_asset_type: 1.3.1 current_balance: 5 previous_balance: 0                         db_maint.cpp:1494
2022-02-19T17:00:00.680 th_a:invoke handle_block schedule_pending_div ] total_fee_per_asset_in_payout_asset: 0 dividend_data.options: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"]                        db_maint.cpp:1534
2022-02-19T17:00:00.712 th_a:invoke handle_block   update_active_sons ] Active SONs set NOT CHANGED                     db_maint.cpp:763
2022-02-19T17:00:00.713 th_a:invoke handle_block         handle_block ] Got block: #47507403 time: 2022-02-19T17:00:00 latency: 713 ms from: eifos-witness  irreversible: 47507396 (-7)                 application.cpp:459

2022-02-18T09:33:11.638 th_a:invoke handle_block push_proposal ] e: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"]

2022-02-18T07:00:03.302 th_a:invoke handle_block   update_active_sons ] Active SONs set NOT CHANGED                     db_maint.cpp:763
2022-02-18T07:00:03.899 th_a:invoke handle_block process_dividend_ass ] In process_dividend_assets time 2019-08-10T19:00:00                     db_maint.cpp:1739
2022-02-18T07:00:03.978 th_a:invoke handle_block schedule_pending_div ] payout_asset_type: 1.3.0 current_balance: 16 previous_balance: 0                        db_maint.cpp:1494
2022-02-18T07:00:03.978 th_a:invoke handle_block schedule_pending_div ] total_fee_per_asset_in_payout_asset: 0 dividend_data.options: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"]                        db_maint.cpp:1534
2022-02-18T07:00:03.984 th_a:invoke handle_block schedule_pending_div ] payout_asset_type: 1.3.1 current_balance: 5550813 previous_balance: 5550790                     db_maint.cpp:1494
2022-02-18T07:00:03.985 th_a:invoke handle_block schedule_pending_div ] total_fee_per_asset_in_payout_asset: 0 dividend_data.options: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"]                        db_maint.cpp:1534
2022-02-18T07:00:04.016 th_a:invoke handle_block   update_active_sons ] Active SONs set NOT CHANGED                     db_maint.cpp:763
2022-02-18T07:00:04.067 th_a:invoke handle_block           operator() ] Exception while modifying object: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"] -- object may be corrupted                 generic_index.hpp:78
2022-02-18T07:00:04.068 th_a:invoke handle_block           operator() ] Exception while modifying object: ["ERROR_WHILE_CONVERTING_VALUE_TO_STRING"] -- object may be corrupted                 generic_index.hpp:78
2022-02-18T07:00:04.325 th_a:invoke handle_block         handle_block ] Got block: #22720000 time: 2019-08-10T19:51:21 latency: 79700923325 ms from: bitcoinsig  irreversible: 22719989 (-11)                   application.cpp:459

impact of this error is not known