diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ScopeUtils.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ScopeUtils.kt
index 71c07bb3c49..b6060bda8fa 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ScopeUtils.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ScopeUtils.kt
@@ -30,7 +30,7 @@ fun ConeKotlinType.scope(useSiteSession: FirSession, scopeSession: ScopeSession)
             // TODO: support that case and switch back to `firUnsafe` instead of `firSafeNullable`
             val fir = this.lookupTag.toSymbol(useSiteSession)?.firSafeNullable<FirRegularClass>() ?: return null
             val companionScope = fir.companionObject?.buildUseSiteScope(useSiteSession, scopeSession)
-            val ownScope = wrapSubstitutionScopeIfNeed(useSiteSession, fir.buildUseSiteScope(useSiteSession, scopeSession), scopeSession)
+            val ownScope = wrapSubstitutionScopeIfNeed(useSiteSession, fir.buildUseSiteScope(useSiteSession, scopeSession)!!, scopeSession)
             if (companionScope != null) FirCompositeScope(mutableListOf(ownScope, companionScope)) else ownScope
 
         }
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SupertypeUtils.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SupertypeUtils.kt
index eb021735c94..428bda63afd 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SupertypeUtils.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SupertypeUtils.kt
@@ -51,9 +51,9 @@ val DECLARED = scopeSessionKey()
 
 data class SubstitutionScopeKey<T : FirClassSubstitutionScope>(val type: ConeClassLikeType) : ScopeSessionKey<T>() {}
 
-fun FirRegularClass.buildUseSiteScope(useSiteSession: FirSession, builder: ScopeSession): FirScope {
+fun FirRegularClass.buildUseSiteScope(useSiteSession: FirSession, builder: ScopeSession): FirScope? {
     val symbolProvider = useSiteSession.service<FirSymbolProvider>()
-    return symbolProvider.getClassUseSiteMemberScope(this.classId, useSiteSession, builder)!!
+    return symbolProvider.getClassUseSiteMemberScope(this.classId, useSiteSession, builder)
 }
 
 fun FirTypeAlias.buildUseSiteScope(useSiteSession: FirSession, builder: ScopeSession): FirScope? {
@@ -72,7 +72,7 @@ fun FirRegularClass.buildDefaultUseSiteScope(useSiteSession: FirSession, builder
                 if (useSiteSuperType is ConeClassErrorType) return@mapNotNull null
                 val symbol = useSiteSuperType.lookupTag.toSymbol(useSiteSession)
                 if (symbol is FirClassSymbol) {
-                    val useSiteScope = symbol.fir.buildUseSiteScope(useSiteSession, builder)
+                    val useSiteScope = symbol.fir.buildUseSiteScope(useSiteSession, builder)!!
                     useSiteSuperType.wrapSubstitutionScopeIfNeed(useSiteSession, useSiteScope, symbol.fir, builder)
                 } else {
                     null