400 Bad Request: {"error":"block param must be a hex int"}

[Matthew]

panic: 400 Bad Request: {"error":"block param must be a hex int"}
On using callBundle

[lmittmann]

What is your value for BlockNumber? nil?

[Matthew]

With a *Big.Int

[lmittmann]

You have to set the BlockNumber param in flashbots.CallBundleRequest. A block tag like "latest" is not allowed by the mev-geth API.