Unexpected DB error occurred near:

Error After Major FUNC: add_update_counter_master_rec for rec_num: 4

--> set_rec_field_str called to set: "last_IP_addr" with value: {{50.16.112.199}}
--> set_rec_field_str called to set: "last_date" with value: {{1427767357}}
--> set_rec_field_str called to set: "S1" with value: {{1}}
--> set_rec_field_str called to set: "S2" with value: {{1427673600}}
--> set_rec_field_str called to set: "S3" with value: {{11}}
--> set_rec_field_str called to set: "S4" with value: {{1427587200}}
--> set_rec_field_str called to set: "S5" with value: {{}}
--> set_rec_field_str called to set: "S6" with value: {{1427068800}}
--> set_rec_field_str called to set: "S7" with value: {{}}
--> set_rec_field_str called to set: "S8" with value: {{1425168000}}
--> set_rec_field_str called to set: "S9" with value: {{}}
--> set_rec_field_str called to set: "S10" with value: {{1420070400}}
--> update_record called
*** get_db_error_msg called to return: Error from cbt level ***
===> ISAM error: Error from cbt level data file: Qfiles/Qcounters.db CBT error: key not found function: cbunlock context: finding leaf containing key ----> update_record function FAILED with error: Error from cbt level

DB Error= 1

Error Record's Field Contents:
4| I| 1| 62928| A| 50.16.112.199| 1427767357| 1| 1427673600| 11| 1427587200| | 1427068800| | 1425168000| | 1420070400| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |