Mapping conflict!how to reindex in the same index pattern

Hello there,

I have a clutser with elasticsearch. I change the type of a field:
%{NUMBER:upload:int}
And now i get the error:
Mapping conflict! 3 fields are defined as several types (string, integer, etc)
As i understood reading on the discussions, i should reindex to get the type of the field.
But i don't want to move the index, i jsut want to continuou with my system as it is.
Just want to reindex, but i don't want to change the pattern logstash-*

In fact, i don't understand clearly the process to reindex.

Any advice would be helpful.

Thanks