disabled btn

src/app/pages/fastcheck-page/fastcheck-page.html

@@ -59,10 +59,10 @@
         }
       </div>
 
-      <!-- Share row — always visible, enabled once amount is known -->
+      <!-- Share row — enabled once a valid fastcheck number is entered, even if there is nothing to pay -->
       <div class="share-row">
         <button type="button" class="share-btn share-btn--tg" (click)="shareByTelegram()"
-                [disabled]="fastcheckAmount() === null || amountLoading()"
+                [disabled]="!canShare()"
                 [title]="'fastcheck.share_tg' | translate">
           <svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
             <path d="M9.04 15.65l-.36 4.06c.51 0 .73-.22.99-.48l2.38-2.27 4.93 3.6c.9.5 1.55.24 1.79-.83l3.24-15.18h.01c.29-1.34-.48-1.86-1.36-1.54L1.13 9.66c-1.32.5-1.3 1.23-.22 1.56l4.92 1.53L17.27 5.6c.54-.34 1.03-.15.62.19"/>

src/app/pages/fastcheck-page/fastcheck-page.ts

@@ -102,6 +102,16 @@ export class FastcheckPage {
       && this.codeEnabled() && !this.amountLoading();
   });
 
+  /**
+   * Share via Telegram is allowed as soon as a valid 18-digit fastcheck is
+   * entered and the lookup is finished — even if there is nothing to pay
+   * (amount is null/zero). Pay button stays governed by canPay().
+   */
+  canShare = computed(() => {
+    const digits = this.fastcheckNumber().replace(/\D/g, '');
+    return digits.length === 18 && !this.amountLoading();
+  });
+
   telegramLink = computed(() => {
     const sid = this.webSessionId();
     return sid