minecraft server crash

---- Minecraft Crash Report ----
// Why did you do that?

Time: 23/02/20 11:45 AM
Description: Exception in server tick loop

com.google.gson.JsonParseException: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 1 column 1 path $
	at abk.a(SourceFile:508)
	at abk.a(SourceFile:524)
	at zs.g(SourceFile:146)
	at wc.z(SourceFile:98)
	at wc.<init>(SourceFile:25)
	at wd.d(SourceFile:186)
	at net.minecraft.server.MinecraftServer.run(SourceFile:628)
	at java.lang.Thread.run(Unknown Source)
Caused by: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 1 column 1 path $
	at com.google.gson.stream.JsonReader.syntaxError(JsonReader.java:1559)
	at com.google.gson.stream.JsonReader.checkLenient(JsonReader.java:1401)
	at com.google.gson.stream.JsonReader.doPeek(JsonReader.java:593)
	at com.google.gson.stream.JsonReader.peek(JsonReader.java:425)
	at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:74)
	at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:61)
	at abk.a(SourceFile:506)
	... 7 more


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- System Details --
Details:
	Minecraft Version: 1.15.2
	Minecraft Version ID: 1.15.2
	Operating System: Windows 10 (x86) version 10.0
	Java Version: 1.8.0_221, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
	Memory: 25221288 bytes (24 MB) / 144306176 bytes (137 MB) up to 1037959168 bytes (989 MB)
	CPUs: 4
	JVM Flags: 1 total; -Xmx1G
	Data Packs:
	Is Modded: Unknown (can't tell)
	Type: Dedicated Server (map_server.txt)