PaymentCardTextField crash fix

[sccainsa]

Proposed changes

It address #796

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• [x ] Bugfix (a non-breaking change which fixes an issue)
• [ ] New feature (a non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality not to work as expected)

Checklist

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• [ ] I have added tests that prove my fix is useful or that my feature works
• [ ] I have added necessary documentation (if appropriate)
• [ ] I know that my PR will be merged only if it has tests and they pass

Further comments

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[cybergrind]

@sccainsa thank you, you can check it in beta version 9.1.3