Prepayments and other current assets (Details) - USD ($)	Mar. 31, 2023	Mar. 31, 2022
Prepayments and other current assets
Prepaid service fees	$ 1,136,769	$ 1,309,069
Prepaid insurance fee		44,519
Prepaid income tax expenses		318,162
Total	$ 1,136,769	$ 1,671,750

Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Name:	us-gaap_PrepaidExpenseCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant