Bg95-m3 at+qiclose=0

Sometimes when I issue the AT+QICLOSE=0 command the modem becomes unresponsive. I noticed it happens when RSSI drops down to -85 dBm. When signal levels are at -60 -70 dBm everything works fine. What would be the reason why the AT+QICLOSE=0 fails at -85dBm?

AT+QISTATE //Confirm and Query Socket Service Status currently
AT+QIGETERROR //Query the Last Error Code