TNS-12531: TNS:cannot allocate memory

hello. I have oracle database 11gr2 that works as "reserve database" . I don'twork on it. it works only for import dump files every midnight. After new year 2016, It does not work... That's my listener error.

<msg time='2016-01-15T13:58:24.850+02:00' org_id='oracle' comp_id='tnslsnr'
type='UNKNOWN' level='16' host_id='deneme-ora.org'
host_addr='UNKNOWN'>
<txt>15-JAN-2016 13:58:24 * 12531
</txt>
</msg>
<msg time='2016-01-15T13:58:24.850+02:00' org_id='oracle' comp_id='tnslsnr'
type='UNKNOWN' level='16' host_id='deneme-ora.org'
host_addr='UNKNOWN'>
<txt>TNS-12531: TNS:cannot allocate memory
</txt>
</msg>

what is the mistake? what can I do.? Oracle;