Irs cant find my taxes i mailed in should i refile

Depends on when you mailed.   The IRS is not currently processing any mailed returns.

Unless you mailed certified with tracking or other tracking service then  there is no way to know if the IRS even received it.  But filing a 2nd return, if both get entered into the IRS processing system, will trigger red flags that will delay processing for months.

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**NOTE*** Due to the Corona virus the IRS is operating short staffed. All field offices are closed and some processing centers are all but closed. Any tax return that requires hand processing will probably have long delays. Mailed returns are not being processed at all at this time. Most phone service has been curtailed.
https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue
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