INCOME TAXES (Details Narrative) - USD ($)	12 Months Ended
May 31, 2023	May 31, 2022	May 31, 2021
Valuation allowance	$ (1,121,000)	$ (278,000)	$ 2,438,000
Federal
Net operating loss carryforward	(46,967,000)	(61,068,000)
Research and development tax credit carryforwards	2,923,000	2,362,000
Alternative minimum tax credit carryforwards	14,425,000
State
Net operating loss carryforward	(30,203,000)	(30,043,000)
Research and development tax credit carryforwards	6,623,000	$ 6,152,000
Alternative minimum tax credit carryforwards	$ 34,000

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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-Topic 740
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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