repo 同步代码 error: Cannot fetch repo

近期同步代码时会报
error: Cannot fetch repo (TypeError: unsupported operand type(s) for +: 'NoneType' and 'str')
Fetching project platform/external/json-c
Exception in thread Thread-229:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 754, in run
self.__target(*self.__args, **self.__kwargs)
File "/home/lidexin/.repo/repo/subcmds/sync.py", line 254, in _FetchProjectList
success = self._FetchHelper(opt, project, *args, **kwargs)
File "/home/lidexin/.repo/repo/subcmds/sync.py", line 297, in _FetchHelper
optimized_fetch=opt.optimized_fetch)
File "/home/lidexin/.repo/repo/project.py", line 1162, in Sync_NetworkHalf
and self._ApplyCloneBundle(initial=is_new, quiet=quiet):
File "/home/lidexin/.repo/repo/project.py", line 1983, in _ApplyCloneBundle
bundle_url = remote.url + '/clone.bundle'
TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'

请问各位有遇到过这种问题吗