Need a little help with kibana visualization

I am using 7.3 of logstash, elasticsearch and kibana on a Windows PC

I am ingesting csv from 5 files, which seems to be working.
My Filter
filter {
csv {
columns => [
"timestamp","uptime","ramused","memused","memfree","memshrd","membuff","memcached","usr","sys","nic","idle","io","irq","sirq","time","nvmramreboot","sdinit","sdcurrent","sdmax","fwversion","ipaddress","devicetype"
]
convert => {
"memused" => "integer"
"memfree" => "integer"
"membuff" => "integer"
"memshrd" => "integer"
"memcached" => "integer"
"sdcurrent" => "integer"
"sdinit" => "integer"
"ramused" => "integer"
"idle" => "float"
"usr" => "float"
"io" => "float"
"nic" => "float"
}
separator => ","
}
}

I can go into Dev Tools, issues a

GET /memleak/_search
{
"query": {
"match_all": {}
}
}

and I get a reasonable output meaning the values from the csv I've converted to integer and float are being displayed as such in the output

I can discover the files and once again get a reasonable output
But I cannot visualize anything beyond a straight count of ingested objects

I converted things like memfree to an integer so I could get metrics like max memfree, or min memfree or average memfree

I created a new visualizer for a Metric. I changed the metric aggregation to Average but Field does not show me any of my integer fields. It says "The index pattern memleak does not contain any of the following compatible field types: number"

I thought that was why I converted the fields to integer, but I guess not.
So, how do I get these to be a 'number' so I can do cool stuff with them?

Thanks!

Could you provide the result of running the following?

GET /memleak/_mapping

Thank you for responding. It's working now, but I cannot honestly tell you why.