diff --git a/src/main/kotlin/org/koitharu/kotatsu/parsers/site/ru/WaMangaParser.kt b/src/main/kotlin/org/koitharu/kotatsu/parsers/site/ru/WaMangaParser.kt
index 2c38420d..85400948 100644
--- a/src/main/kotlin/org/koitharu/kotatsu/parsers/site/ru/WaMangaParser.kt
+++ b/src/main/kotlin/org/koitharu/kotatsu/parsers/site/ru/WaMangaParser.kt
@@ -101,7 +101,7 @@ internal class WaMangaParser(
 					number = it.getFloatOrDefault("chapter", 0f),
 					volume = it.getIntOrDefault("volume", 0),
 					name = it.getStringOrNull("full_title") ?: manga.title,
-					scanlator = it.getJSONArray("teams").optJSONObject(0, null)?.getStringOrNull("name"),
+					scanlator = it.getJSONArray("teams").getJSONObject(0)?.getStringOrNull("name"),
 					uploadDate = dateFormat.tryParse(it.getStringOrNull("published_on")),
 					branch = null,
 				)
diff --git a/src/main/kotlin/org/koitharu/kotatsu/parsers/site/vi/CMangaParser.kt b/src/main/kotlin/org/koitharu/kotatsu/parsers/site/vi/CMangaParser.kt
index 6fef8031..ec8c3156 100644
--- a/src/main/kotlin/org/koitharu/kotatsu/parsers/site/vi/CMangaParser.kt
+++ b/src/main/kotlin/org/koitharu/kotatsu/parsers/site/vi/CMangaParser.kt
@@ -1,7 +1,6 @@
 package org.koitharu.kotatsu.parsers.site.vi
 
 import androidx.collection.ArrayMap
-import androidx.collection.ArraySet
 import org.json.JSONObject
 import org.koitharu.kotatsu.parsers.MangaLoaderContext
 import org.koitharu.kotatsu.parsers.MangaParserAuthProvider
@@ -24,7 +23,11 @@ import org.koitharu.kotatsu.parsers.util.domain
 import org.koitharu.kotatsu.parsers.util.generateUid
 import org.koitharu.kotatsu.parsers.util.getCookies
 import org.koitharu.kotatsu.parsers.util.json.asTypedList
+import org.koitharu.kotatsu.parsers.util.json.getStringOrNull
 import org.koitharu.kotatsu.parsers.util.json.mapJSON
+import org.koitharu.kotatsu.parsers.util.json.mapJSONNotNull
+import org.koitharu.kotatsu.parsers.util.mapNotNullToSet
+import org.koitharu.kotatsu.parsers.util.nullIfEmpty
 import org.koitharu.kotatsu.parsers.util.parseJson
 import org.koitharu.kotatsu.parsers.util.parseJsonArray
 import org.koitharu.kotatsu.parsers.util.parseRaw
@@ -34,7 +37,6 @@ import org.koitharu.kotatsu.parsers.util.toTitleCase
 import org.koitharu.kotatsu.parsers.util.tryParse
 import org.koitharu.kotatsu.parsers.util.urlBuilder
 import java.text.SimpleDateFormat
-import java.time.Instant
 import java.util.EnumSet
 import java.util.Locale
 
@@ -92,11 +94,11 @@ internal class CMangaParser(context: MangaLoaderContext) :
 				.mapJSON { jo ->
 					val chapterId = jo.getLong("id_chapter")
 					val info = jo.parseJson("info")
-					val chapterNumber = info.getInt("num")
+					val chapterNumber = info.getString("num")
 					MangaChapter(
 						id = generateUid(chapterId),
 						name = if (info.isLocked()) "Chapter $chapterNumber - locked" else "Chapter $chapterNumber",
-						number = chapterNumber + 1f,
+						number = chapterNumber.toFloatOrNull()?.plus(1) ?: 0f,
 						volume = 0,
 						url = "/album/$slug/chapter-$mangaId-$chapterId",
 						uploadDate = df.tryParse(info.getString("last_update")),
@@ -141,33 +143,32 @@ internal class CMangaParser(context: MangaLoaderContext) :
 			webClient.httpGet(url).parseJsonArray()
 		}
 
-		return mangaList.mapJSON { jo ->
+		return mangaList.mapJSONNotNull { jo ->
 			val info = jo.parseJson("info")
-			val slug = info.getString("url")
-			val id = info.getLong("id")
+			val slug = info.getStringOrNull("url") ?: return@mapJSONNotNull null
+			val id = info.optLong("id").takeIf { it != 0L } ?: return@mapJSONNotNull null
 			val relativeUrl = "/album/$slug-$id"
-			val mangaTags = ArraySet<MangaTag>()
-			info.getJSONArray("tags").asTypedList<String>().forEach {
-				tags.get()[it.lowercase()]?.let { mangaTags.add(it) }
-			}
 
 			Manga(
 				id = generateUid(id),
-				title = info.getString("name").toTitleCase(),
-				altTitle = info.getJSONArray("name_other").asTypedList<String>().joinToString(),
+				title = info.optString("name").toTitleCase(),
+				altTitle = info.optJSONArray("name_other")?.asTypedList<String>()?.joinToString()?.nullIfEmpty(),
 				url = relativeUrl,
 				publicUrl = relativeUrl.toAbsoluteUrl(domain),
 				rating = RATING_UNKNOWN,
 				isNsfw = false,
 				coverUrl = "/assets/tmp/album/${info.getString("avatar")}".toAbsoluteUrl(domain),
-				tags = mangaTags,
-				state = when (info.getString("status")) {
+				tags = info.optJSONArray("tags")?.asTypedList<String>()
+					?.mapNotNullToSet { tags.get()[it.lowercase()] }
+					.orEmpty(),
+				state = when (info.optString("status")) {
 					"doing" -> MangaState.ONGOING
-					else -> null // can't find any manga with other status than on going
+					"done" -> MangaState.FINISHED
+					else -> null
 				},
 				author = null,
 				largeCoverUrl = null,
-				description = info.optString("detail"),
+				description = info.getStringOrNull("detail")?.replace("\\\"", "\""),
 				chapters = emptyList(),
 				source = source,
 			)