Loans - Activity in the allowance for loan losses by portfolio segment (Details) - USD ($)	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	$ 2,186,182	$ 1,699,977
Recoveries	8,868	486,205
Balance at end of year	2,195,050	2,186,182
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	2,195,050	2,186,182
Balance at end of period	2,195,050	2,186,182
Loans - Individually evaluated for impairment	193,385	539,423
Loans - Collectively evaluated for impairment	187,707,089	146,334,172
Loans - Balance at end of period	187,900,474	146,873,595
Commercial real estate [Member] \| Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	1,036,301	274,997
Recoveries		65,293
Provisions	555,343	696,011
Balance at end of year	1,591,644	1,036,301
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	1,591,644	1,036,301
Balance at end of period	1,591,644	1,036,301
Loans - Individually evaluated for impairment		223,983
Loans - Collectively evaluated for impairment	80,603,153	51,924,082
Loans - Balance at end of period	80,603,153	52,148,065
Commercial [Member] \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	157,533	1,021,083
Recoveries		341,388
Provisions	(124,832)	(1,204,938)
Balance at end of year	32,701	157,533
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	32,701	157,533
Balance at end of period	32,701	157,533
Loans - Collectively evaluated for impairment	8,778,723	19,278,477
Loans - Balance at end of period	8,778,723	19,278,477
Commercial [Member] \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	59,649	43,858
Recoveries		73,128
Provisions	(4,620)	(57,337)
Balance at end of year	55,029	59,649
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	55,029	59,649
Balance at end of period	55,029	59,649
Loans - Collectively evaluated for impairment	10,582,488	7,985,188
Loans - Balance at end of period	10,582,488	7,985,188
Residential [Member] \| One-to-four-family residential
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	409,395	339,449
Recoveries		549
Provisions	(145,444)	69,397
Balance at end of year	263,951	409,395
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	263,951	409,395
Balance at end of period	263,951	409,395
Loans - Individually evaluated for impairment	193,385	315,440
Loans - Collectively evaluated for impairment	51,697,563	48,089,380
Loans - Balance at end of period	51,890,948	48,404,820
Residential [Member] \| Multi-family real estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	134,216	10,057
Provisions	99,155	124,159
Balance at end of year	233,371	134,216
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	233,371	134,216
Balance at end of period	233,371	134,216
Loans - Collectively evaluated for impairment	33,944,903	17,268,048
Loans - Balance at end of period	33,944,903	17,268,048
Consumer Loans [Member] \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	4,896	2,003
Recoveries	8,868	5,847
Provisions	(13,163)	(2,954)
Balance at end of year	601	4,896
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	601	4,896
Balance at end of period	601	4,896
Loans - Collectively evaluated for impairment	2,100,259	1,788,997
Loans - Balance at end of period	2,100,259	1,788,997
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year	384,192	8,530
Provisions	(366,439)	375,662
Balance at end of year	17,753	384,192
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively evaluated for impairment	17,753	384,192
Balance at end of period	$ 17,753	$ 384,192

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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