The software utilizes the checkm8 bootrom exploit. This is a hardware-level vulnerability found in Apple devices ranging from the iPhone 4s to the iPhone X (including the iPad 2).
Open iRemove Tools and click the "Bypass" button. The software will run a script that modifies the startup sequence. iremove tools 128 ipad 2 link
If the iPad 2 is legitimately yours (or you have the receipt), the safest and most permanent method is to contact Apple Support. Even though the device is old, Apple can remove the Activation Lock if you provide proof of ownership. This ensures the device works perfectly with all features (iCloud, App Store, etc.) afterwards. The software utilizes the checkm8 bootrom exploit