Error while encoding

I get the following error and I don't know why, all my variables are strings.

java.lang.RuntimeException: Error while encoding: java.lang.RuntimeException: java.lang.Double is not a valid external type for schema of int if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, validateexternaltype(getexterna...

Thanks

Hi @helvmrc
Post "Diagnostic Info" from Admin > Troubleshooting.
What exactly are you doing to trigger this problem?
The error looks like a problem between Double and Integer - not strings - but it would be helpful with the full stacktrace.