An exception was thrown whilst checking the command queue

(22:23:21) | [Tebex Donate] An exception was thrown whilst logging player connection events: Unexpected character encountered while parsing value: <. Path '', line 0, position 0.

(22:23:21) | [Tebex Donate] Associated response: <html>

<head><title>504 Gateway Time-out</title></head>

<body bgcolor="white">

<center><h1>504 Gateway Time-out</h1></center>

<hr><center>nginx</center>

</body>

</html>

(22:23:21) | [Tebex Donate] at Newtonsoft.Json.JsonTextReader.ParseValue () [0x002b3] in <2ae3f091decd4989b3c4d466e6eb5985>:0

at Newtonsoft.Json.JsonTextReader.Read () [0x0004c] in <2ae3f091decd4989b3c4d466e6eb5985>:0

at Newtonsoft.Json.Linq.JObject.Load (Newtonsoft.Json.JsonReader reader, Newtonsoft.Json.Linq.JsonLoadSettings settings) [0x00013] in <2ae3f091decd4989b3c4d466e6eb5985>:0

at Newtonsoft.Json.Linq.JObject.Parse (System.String json, Newtonsoft.Json.Linq.JsonLoadSettings settings) [0x0000c] in <2ae3f091decd4989b3c4d466e6eb5985>:0

at Newtonsoft.Json.Linq.JObject.Parse (System.String json) [0x00000] in <2ae3f091decd4989b3c4d466e6eb5985>:0

at Oxide.Plugins.TebexDonate+<LogEvents>c__AnonStorey2.<>m__1 (System.Int32 code, System.String response) [0x000a6] in <9ba2300bde2d4c72bf19fc463e639391>:0

same issue here

I get this error every time I start the server.

Same issues occurring 

[Tebex Donate] An exception was thrown whilst checking the command queue: Unexpected character encountered while parsing value: <. Path '', line 0, position 0.
04/05 14:51:00 | [Tebex Donate] Associated response: <html>
<head><title>524 Origin Time-out</title></head>
<body bgcolor="white">
<center><h1>524 Origin Time-out</h1></center>
<hr><center>cloudflare-nginx</center>
</body>
</html>
04/05 14:51:00 | [Tebex Donate] at Newtonsoft.Json.JsonTextReader.ParseValue () [0x002b3] in <2ae3f091decd4989b3c4d466e6eb5985>:0
at Newtonsoft.Json.JsonTextReader.Read () [0x0004c] in <2ae3f091decd4989b3c4d466e6eb5985>:0
at Newtonsoft.Json.Linq.JObject.Load (Newtonsoft.Json.JsonReader reader, Newtonsoft.Json.Linq.JsonLoadSettings settings) [0x00013] in <2ae3f091decd4989b3c4d466e6eb5985>:0
at Newtonsoft.Json.Linq.JObject.Parse (System.String json, Newtonsoft.Json.Linq.JsonLoadSettings settings) [0x0000c] in <2ae3f091decd4989b3c4d466e6eb5985>:0
at Newtonsoft.Json.Linq.JObject.Parse (System.String json) [0x00000] in <2ae3f091decd4989b3c4d466e6eb5985>:0
at Oxide.Plugins.TebexDonate.<CheckCommandQueue>m__0 (System.Int32 code, System.String response) [0x0000c] in <adaa2a773fa44a749440b709929e81ca>:0