[BUG]: 'NAN' Displayed After Removing '0' from Price Text Box and Clicking on (-1%) Button; Characters Allowed After 'NAN' Displayed

[ShantanuSharma9873]

Summary:
When the user removes the '0' from the Price text box and then clicks on the (-1%) button in the DEX tab, 'NAN' is displayed in the Price field. Additionally, after 'NAN' appears, characters can be entered into the Price field, which was previously restricted.

To Reproduce
Steps to reproduce the behavior:

1. Login to the Wallet.
2. Move to the DEX tab
3. Remove the '0' from the Price text box.
4. Click on the "-1%" Button.
5. Notice that 'NAN' is displayed at the Price field and also at other places.

Tested on - komodo-wallet-windows-release-070cf55.zip
Of PR - https://github.com/KomodoPlatform/komodo-wallet-desktop/pull/2472

NAN_Issue.mp4

Additional context
Issue also occurred on:
Application Version - 0.7.2-beta
MM2 Version - 2.1.0-beta_2.1.23_gs/v2.1.0-beta_35e923949_Windows_NT_Release

[ShantanuSharma9873]

The issue still occurs on: