ORA-00376: file 24 cannot be read at this time
ORA-01110: data file 24: '+DATA/devdb/datafile/conv_index.425.774183213'
00376. 00000 -  "file %s cannot be read at this time"
*Cause:    attempting to read from a file that is not readable. Most likely
           the file is offline.
*Action:   Check the state of the file. Bring it online

[DEV] SYS@devdb> select file_name,status,online_status  from dba_data_files where tablespace_name=conv_index';

FILE_NAME
--------------------------------------------------------------------------------
STATUS    ONLINE_
--------- -------
+DATA/devdb/datafile/conv_index.425.774183213
AVAILABLE RECOVER

Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
AUTO
Log applied.
Media recovery complete.

+DATA/devdb/datafile/conv_index.425.774183213
AVAILABLE ONLINE