Is oracle dbms_crypto.randomnumber secure?

Hello stack community,

• I did key generator some thime ago using dbms_crypto.randomnumber.
• Im picking chars in a loop via random number from my set.

The thing is, random functions in dbms_crypto are based on the RSA X9.31 PRNG (Pseudo-Random Number Generator). And NIST says:

The Random Number Generators specified in FIPS 186-2 with Change Notice 1 >dated October 5, 2001 (Appendix 3.1 and 3.2), ANSI X9.31 (Appendix A.2.4) and >ANSI X9.62 (Appendix A.4)are no longer compliant as of January 1, 2016.

And i wonder:

• Is it sercure to continue to generate randomnumber or convert it from randombytes in oracle?

• Is there a valid secure way to do this? Or should i just change the platform i generate these codes?

i need some enlightenment about this. My key generator in the below

i            number;
charSet      varchar2(64) := '0123456789ABCDEFGHIJKLMNOPQRSTUXWVYZabcdefghijklmnopqrstuvwxyz++';
output       varchar2(16);
selectedChar char;--begin below

output := data;
if (output is null or length(output) <> 16) then
  selectedChar := substr(charSet, MOD(dbms_crypto.randomnumber, 64), 1);
  if selectedChar <> '+' then
    output := output || selectedChar;
  else
    return generateSecureCode(output);
  end if;
  return generateSecureCode(output);
else
  --dbms_output.put_line(output);
  select count(*)
    into i
    FROM [a table] b
   WHERE b.secure_code = output;
  if i > 0 then
    return generateSecureCode(null);
  end if;
  return output;
end if;