CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($)	9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019
Cash flows from operating activities:
Net loss	$ (1,852,482)	$ (1,607,730)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	94,772	128,114
Change in provision for allowance on accounts receivable	3,571	13,192
Inventory reserve	5,684	7,249
Stock option expense	192,917	146,514
Reduction (increase)_ in deferred rent liability	(37,971)	5,360
Amortization of right-of-use asset	213,032
Changes in assets and liabilities:
Accounts receivable	488,759	(290,727)
Inventories	(42,199)	91,244
Prepaid expenses and other	4,898	46,772
Reduction in lease liability	(150,485)
Other assets	(689)	(8,984)
Accounts payable and accrued expenses	268,068	197,386
Accrued compensation	9,214	13,902
Net cash used in operating activities	(802,911)	(1,257,708)
Cash flows from investing activities:
Increase in intangibles	(23,933)	(46,226)
Purchases of property and equipment	(27,724)	(72,947)
Net cash used in investing activities	(51,657)	(119,173)
Net cash flows from financing activities:
Proceeds from sales of common stock, net	366,258	1,011,636
Proceeds from sale of convertible preferred stock, net	1,917,586
Proceeds from exercise of stock options	79,828	82,990
Proceeds from equity financing-officer	200,000
Common stock subscribed		2,672
Net cash provided by financing activities	2,563,672	1,097,298
Effect of exchange rate changes in cash	(4,157)	(7,385)
Net increase (decrease) in cash and cash equivalents	1,704,947	(286,968)
Cash and cash equivalents at beginning of period	686,785	1,204,903
Cash and cash equivalents at end of period	2,391,732	917,935
Cash paid during the period for:
Interest	9	47
Income taxes	12,170
Non-cash Investing and Financing Activities:
Establishment of Right-of-Use Asset per ASC 842	1,942,999
Establishment of Lease Liability per ASC 842	$ 1,980,970