When using Axure rp11 to open a file created in rp9, it prompts "This is not a valid Axure RP file"

Axure RP 11
1

When using Axure rp11 to open a file created in rp9, it prompts “This is not a valid Axure RP file”，How to solve it？

2

暂时的解决方案供参考：用RP10转换一次，然后再用RP11转换一次。
Temporary solution for reference: convert once with RP10 and then again with RP11.