Income taxes (Restated) (Details) - Schedule of deferred tax assets - USD ($)	Sep. 30, 2020	Jun. 30, 2020
Net operating loss
Total deferred tax assets	$ 7,733,000	$ 7,463,000
Valuation allowance	(7,733,000)	(7,463,000)
Deferred tax assets, net - long-term
U.S. [Member]
Allowance for doubtful accounts
Allowance for doubtful accounts	1,331,000	1,329,000
Net operating loss
Net operating loss	1,906,000	1,756,000
PRC [Member]
Allowance for doubtful accounts
Allowance for doubtful accounts	3,005,000	2,888,000
Net operating loss
Net operating loss	$ 1,491,000	$ 1,490,000