rubyプログラム実行中に発生するエラーの解決方法を教えてください。

下記のビットコイントレードのプログラムを実行中に一定時間が経過するとエラーが発生してしまいます。
途中でapiに接続できなくなったということかと思いますが、
何か解決方法はあるのでしょうか？

発生している問題・エラーメッセージ

Traceback (most recent call last):
	11: from bitcoin_trade.rb:9:in `<main>'
	10: from bitcoin_trade.rb:9:in `loop'
	 9: from bitcoin_trade.rb:22:in `block in <main>'
	 8: from /Users/workspace/bitcoin_trade/method.rb:143:in `getcollateral'
	 7: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:1455:in `request'
	 6: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:909:in `start'
	 5: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:920:in `do_start'
	 4: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:935:in `connect'
	 3: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/timeout.rb:103:in `timeout'
	 2: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/timeout.rb:93:in `block in timeout'
	 1: from /Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:936:in `block in connect'
/Users/.rbenv/versions/2.5.0/lib/ruby/2.5.0/net/http.rb:939:in `rescue in block in connect': Failed to open TCP connection to api.bitflyer.com:443 (No route to host - connect(2) for "api.bitflyer.com" port 443) (Errno::EHOSTUNREACH)

該当のソースコード

ruby
1require "./method"
2require "date"
3
4# トリガー出来高
5@v = 30
6# トレーリング幅
7@margin = 500
8
9loop do
10  # 約定データの有無確認
11  getexecutions
12  if @length != 0
13    # データがある場合、自身の建玉一覧取得
14    getpositions
15    if @getpositions_hash.empty?
16      # 建玉がない場合、出来高合計値を算出
17      volume = 0
18      for i in 0..@length-1
19        volume = volume + @getexecutions_hash[i]["size"]
20      end
21      # 直近の出来高が一定数量以上の場合、新規建て注文を発注する
22      getcollateral
23      if volume > @v
24        # 最新価格と最古価格の価格差算出
25        price_margin = @getexecutions_hash[0]["price"]-@getexecutions_hash[@length-1]["price"]
26        # 価格差がプラスの場合、買建て注文発注
27        getboard
28        if price_margin > 0
29          buy
30          @settlement_price = @getboard_hash["mid_price"] - @margin
31          print Time.now,"/新規買/直近価格：",@getboard_hash["mid_price"],"円/証拠金：",@collateral = @getcollateral_hash["collateral"],"円"
32          puts ""
33          sleep(2)
34        # 価格差がマイナスの場合、売建て注文発注
35        elsif price_margin < 0
36          sell
37          @settlement_price = @getboard_hash["mid_price"] + @margin
38          print Time.now,"/新規売/直近価格：",@getboard_hash["mid_price"],"円/証拠金：",@collateral = @getcollateral_hash["collateral"],"円"
39          puts ""
40          sleep(2)
41        end
42      end
43    # 建玉がある場合
44    else
45      # sideに応じて決済注文発注
46      # 売り決済
47      getboard
48      if @getpositions_hash[0]["side"] == "BUY"
49        if @settlement_price > @getboard_hash["mid_price"]
50          sell
51          print Time.now,"/売決済/直近価格：",@getboard_hash["mid_price"],"円"
52          sleep(2)
53          getcollateral
54          print "/証拠金：",@getcollateral_hash["collateral"],"円/損益：",@getcollateral_hash["collateral"]-@collateral
55          puts ""
56        else
57          if @settlement_price + @margin < @getboard_hash["mid_price"]
58            print Time.now,",",@settlement_price = @getboard_hash["mid_price"] - @margin,"円"
59            puts ""
60          end
61        end
62        # 買い決済の場合
63      else
64        if @settlement_price < @getboard_hash["mid_price"]
65          buy
66          print Time.now,"/買決済/直近価格：",@getboard_hash["mid_price"],"円"
67          sleep(2)
68          getcollateral
69          print "/証拠金：",@getcollateral_hash["collateral"],"円/損益：",@getcollateral_hash["collateral"]-@collateral
70          puts ""
71        else
72          if @settlement_price - @margin > @getboard_hash["mid_price"]
73            print Time.now,",",@settlement_price = @getboard_hash["mid_price"] + @margin,"円"
74            puts ""
75          end
76        end
77      end
78    end
79  end
80  sleep(2)
81end
82