This is an intermittent issue, where your IDE bot type is changed to some undefined value which is not supported to link with your Access API App that you have created on our platform. Hence, the bot-app linkage issue.
Alternative Solution: Till the issue is fixed, as an immediate solution, you can use this workaround to resolve your issue:
1. Create a new bot on our platform of type IDE.
2. Copy-Paste all bot code(index.js, default.src, default.js, and any other dependent file you have created in the bot project folder) from old bot to new bot.
3. Deploy the bot on prod.
4. Go to your App settings page and link the new bot.
For more details on this issue, you can write to us at firstname.lastname@example.org