OSError: [Errno 28] No space left on device

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/user/wspace/electrum/.buildozer/android/app/electrum/gui/qml/qeconfig.py", line 276, in lightningPaymentFeeMaxMillionths
  File "/home/user/wspace/electrum/.buildozer/android/app/electrum/simple_config.py", line 111, in _set_config_value
  File "/home/user/wspace/electrum/.buildozer/android/app/electrum/simple_config.py", line 301, in set_key
  File "/home/user/wspace/electrum/.buildozer/android/app/electrum/simple_config.py", line 311, in _set_key_in_user_config
  File "/home/user/wspace/electrum/.buildozer/android/app/electrum/simple_config.py", line 424, in save_user_config
OSError: [Errno 28] No space left on device