LED Driver CAT4139 - LED always on

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hello,
i wanted ask if has experience led driver onsemi cat4139 (datasheet here), because  can't work properly.
the problem led stays on, no matter if shdn (shutdown) pin of cat4139 high or low is. pwm on shdn led same brightness , current draw.
the shdn pin goes directly atmega328 3.3v pwm pin d9. not sure if needed resistor in between, tried putting 1kohm, no change. checking voltage on shdn, see correctly goes high , low when mcu executes digitalwrite(led, high) , digitalwrite(led, low).
the power "pwr" comes li-ion @ 3.8v.
i've tried connect r6 (=r1 in datasheet) gnd directly gnd pin of cat4139, suggested in datasheet, no change.
if swap r6 (10 ohm) 4.3 ohm, see higher current draw , brightness, expected.
i checked connection multimeter , fine.
do have idea wrong? i've tried 3 cat4139, on 2 boards , same result. board  first pcb , don't have esd safe bench.
i'm interested in understanding if did mistake schematic.
does see obvious? maybe shdn pin turn off cat4139, not led? strange, right?
please find attached images circuit schema.
any feedback appreciated.

thank much
sincerely

are sure ground plane extended both chip , c6? looks island.


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