Pay attention to the message:
"Either the data contains characters that are not representable in the new encoding or truncation occurred during transcoding."
Run next code and check your encoding option printed in the log:
proc options option=encoding; run;
it seems that the imported data contains characters that are presented by 2 bytes or more
and the encoding option in your sas does not support it.
add to FILENAME statement (or INFILE statement) the option encoding=UTF8;
If you have more questions about please post your importing data code and your sas system encoding.