Название формы поменено.

SushiBar/SushiBar/FormMain.cs

@@ -169,8 +169,8 @@ namespace SushiBarView
 
         private void ButtonAddSushiInShop_Click(object sender, EventArgs e)
         {
-            var service = Program.ServiceProvider?.GetService(typeof(FormAddSushiInShop));
-            if (service is FormAddSushiInShop form)
+            var service = Program.ServiceProvider?.GetService(typeof(FormShopSushi));
+            if (service is FormShopSushi form)
             {
                 form.ShowDialog();
             }

SushiBar/SushiBar/FormShopSushi.Designer.cs

@@ -1,6 +1,6 @@
 namespace SushiBarView
 {
-    partial class FormAddSushiInShop
+    partial class FormShopSushi
     {
         /// <summary>
         /// Required designer variable.
@@ -116,7 +116,7 @@
             this.buttonSave.UseVisualStyleBackColor = true;
             this.buttonSave.Click += new System.EventHandler(this.ButtonSave_Click);
             // 
-            // FormAddSushiInShop
+            // FormShopSushi
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(7F, 15F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
@@ -129,7 +129,7 @@
             this.Controls.Add(this.labelSushi);
             this.Controls.Add(this.comboBoxShop);
             this.Controls.Add(this.labelShop);
-            this.Name = "FormAddSushiInShop";
+            this.Name = "FormShopSushi";
             this.Text = "Поступление суши в суши-бар";
             ((System.ComponentModel.ISupportInitialize)(this.numericUpDownCount)).EndInit();
             this.ResumeLayout(false);

SushiBar/SushiBar/FormShopSushi.cs

@@ -4,7 +4,7 @@ using SushiBarContracts.ViewModels;
 
 namespace SushiBarView
 {
-    public partial class FormAddSushiInShop : Form
+    public partial class FormShopSushi : Form
     {
         private readonly ILogger _logger;
         private readonly IShopLogic _shopLogic;
@@ -12,7 +12,7 @@ namespace SushiBarView
         private readonly List<ShopViewModel>? _listShops;
         private readonly List<SushiViewModel>? _listSushi;
 
-        public FormAddSushiInShop(ILogger<FormAddSushiInShop> logger, IShopLogic shopLogic, ISushiLogic sushiLogic)
+        public FormShopSushi(ILogger<FormShopSushi> logger, IShopLogic shopLogic, ISushiLogic sushiLogic)
         {
             InitializeComponent();
             _shopLogic = shopLogic;

SushiBar/SushiBar/Program.cs

@@ -52,7 +52,7 @@ namespace SushiBarView
             services.AddTransient<FormSushi>();
             services.AddTransient<FormSushiIngredients>();
             services.AddTransient<FormListSushi>();
-            services.AddTransient<FormAddSushiInShop>();
+            services.AddTransient<FormShopSushi>();
             services.AddTransient<FormShops>();
             services.AddTransient<FormShop>();
         }