I got this error today and after a few minutes of messing around with FileZilla settings I discovered a way around it. This might not work for everyone, but it worked for me.
Error: GnuTLS error -53: Error in the push function.
I had my “Encryption” setting set to “Require implicit FTP over TLS”, when I switch that to “Require explicit FTP over TLS” it works.
You might be prompted to accept a certificate.
Jon