Are you referring to the "Get My Payment" tool re: the stimulus at the IRS website, and saying it cannot find your info?
That tool can be quirky.
Uses dashes in the SSN.
Try using all capital letters.
Do not use any punctuation in the address.
Try the address exactly as it appears on your 2018 return.
Or if that doesn't work, look up the official address styling at the USPS website below: