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Common Stock (Details Narrative) - USD ($)					3 Months Ended	12 Months Ended
	Oct. 24, 2019	Apr. 08, 2019	Jan. 07, 2019	Aug. 13, 2018	Apr. 30, 2020	Apr. 30, 2020	Apr. 30, 2019
Common stock, shares authorized					100,000,000	100,000,000	100,000,000
Common stock, par value					$ 0.001	$ 0.001	$ 0.001
Common stock, shares issued					12,939,420	12,939,420	5,425,517
Number of common stock shares sold		1,542,000
Aggregate offering price		$ 15,700,000
Pre-funded Warrants [Member]
Warrant to purchase shares common stock		3,385,680
Over-Allotment Option [Member]
Number of common stock shares sold		642,000
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member]
Aggregate purchase of common stock	$ 10,000,000			$ 10,000,000
Percentage of outstanding common stock limit for shareholder approval				19.99%
Number of shares can be issued based upon outstanding percentage				183,591
Common stock issued for commitment fee				21,429
Number of common stock shares sold	162,162
Value of common stock shares sold, net of issuance costs	$ 949,259
Sale of stock, price per share	$ 5.85
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member] | December 20, 2019 [Member]
Stock issued for new issue, shares	5,400,000
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member] | Maximum [Member]
Percentage of outstanding common stock limit for shareholder approval	19.99%
Number of shares can be issued based upon outstanding percentage	1,219,010
Common stock issued for commitment fee	194,805
Sale of stock, price per share					$ 0.82	$ 0.82
Stock issued for new issue, shares					1,399,205	1,399,205
Stock issued for new issue, value					$ 1,100,000	$ 1,100,000
2019 ATM Facility [Member] | A.G.P./ Alliance Global Partners [Member]
Number of common stock shares sold						5,101,405
Value of common stock shares sold, net of issuance costs						$ 3,800,000
Sale of stock, price per share					$ 0.74	$ 0.74
Aggregate offering price			$ 25,000,000
Payment of sales commission						$ 122,530
Securities Purchase Agreement [Member]
Warrant to purchase shares common stock		4,927,680

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