Sister had power or attorney and won't tell me any thing also her husband shedered all her paper work the day after death
If your Mom tried to name you as beneficiary on her 401k, her husband would have had to sign something to give permission not to be the beneficiary. With 401k money, the spouse is, by law, assumed to be the beneficiary and has to give written permission for someone else to be named. Your mother naming you as beneficiary isn't, by itself, enough with a 401k. (It probably would have been enough with an IRA.)
Also, if your sister was your Mom's agent via a Power of Attorney, your sister may have been able to change beneficiaries after Mom had done so. That depends on what powers were given to your sister in the POA.
If you wish to pursue this further, you will need an attorney.
Is the "husband" your refer to you mom or your mother's husband. Get a copy of the death certificate and communicate directly with her former employer. They can tell you whether you are a named beneficiary.
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