Correct Beginning balance on loan schedule

[GINMED]

Hi,

I need your advice, how to correctly calculate beginning balance in lean amortization schedule.

Therre is my data, wich has interest payment, but there is unusually case - 1st interest payment is currnet amount.

ID	Start Date	End Date	PV	1st interest pament	Rate	Freq of payment	Rate in period
111111	13.04.2021	12.12.2023	6001,99	61,49	0,20489	12	0,017074167

There is may measure for beginning balance, but it does not calculate correct interest payments depending on 1st payment :

Beginning Balance =

Var PV = sum('Table'[PV])

Var Interest = SELECTEDVALUE('Table'[Rate in period])

Var Index = SELECTEDVALUE('Project'[Sequence])

Var Payment = MIN('Table'[Rent payment])

Var Result =

             if(PV *

                     POWER( 1 + Interest, Index - 1 ) - Payment * DIVIDE( POWER( 1 + Interest, Index- 1 ) - 1 , Interest) >= 0,

                PV *  POWER( 1 + Interest , Index - 1 ) - Payment * DIVIDE( POWER( 1 + Interest, Index- 1 ) - 1 ,Interest),0) RETURN Result

Expected result:

Sequence	Starting Balance	Interest	Principal	Ending Balance
1	6001,99259	61,49	214,07	5849,41259
2	5849,41259	99,87	356,78	5592,50259
3	5592,50259	95,49	356,78	5331,21259
4	5331,21259	91,03	356,78	5065,46259
5	5065,46259	86,49	356,78	4795,17259
6	4795,17259	81,87	356,78	4520,26259
7	4520,26259	77,18	356,78	4240,66259
8	4240,66259	72,41	356,78	3956,29259
9	3956,29259	67,55	356,78	3667,06259
10	3667,06259	62,61	356,78	3372,89259
11	3372,89259	57,59	356,78	3073,70259
12	3073,70259	52,48	356,78	2769,40259
13	2769,40259	47,29	356,78	2459,91259
14	2459,91259	42	356,78	2145,13259
15	2145,13259	36,63	356,78	1824,98259
16	1824,98259	31,16	356,78	1499,36259
17	1499,36259	25,6	356,78	1168,18259
18	1168,18259	19,95	356,78	831,3525902
19	831,3525902	14,18	356,78	488,7525902
20	488,7525902	8,34	356,78	140,3125902
21	140,3125902	2,4	142,71	0,002590196

How can I switch interest payments in my schedule project to get correct beggining balance??

Thaks in advance

[GINMED]