In older flows I have built with same action invoked, there's no issue to execute. And now I use the same action in a new flow, it failed with below error. I am not sure there's something changed at background by MS.
OpenApiOperationParameterTypeConversionFailed. The 'inputs.parameters' of workflow operation 'Post_a_reply_to_a_message_(V2)_2' of type 'OpenApiConnection' is not valid. Error details: Input parameter 'messageId' is required to be of type 'Integer/int32'. The runtime value '1576006164768' to be converted doesn't have the expected format 'Integer/int32'.
Below is a part of the flow. I would first get messages from a Teams channel and loop through for a specific one then save its message ID, which to be stored into variable 'oriMsgId' with expression 'body('Get_messages')?['Value']?[iterationIndexes('Do_until')]?['id']'. And this 'oriMsgId' would be used as message Id parameter in 'Post a reply to a mesage (V2)' action. Error thrown at that action block when the flow runs.