Grafana + Zabbix: API rpc error: string field contains invalid UTF-8

I can’t connect to the Zabbix data source, errors appear in the graphana log:

t=2021-02-25T08:28:03-0300 lvl=dbug msg="Querying for data source via SQL store" logger=datasources id=1 orgId=1
t=2021-02-25T08:28:03-0300 lvl=eror msg="Failed to call resource" logger=context userId=1 orgId=1 uname=admin error="**Failed to call resource: rpc error: code = Internal desc = grpc: error while marshaling: string field contains invalid UTF-8**"
t=2021-02-25T08:28:03-0300 lvl=eror msg="Request Completed" logger=context userId=1 orgId=1 uname=admin method=POST path=/api/datasources/1/resources/zabbix-api status=500 remote_addr=192.168.
13.7 time_ms=4 size=37 referer=https://zbx.unipam.edu.br/grafana/datasources/edit/1/

How do I solve this problem: rpc error: code = Internal desc = grpc: error whil
and marshaling: string field contains invalid UTF-8 "?