So in the custom components folder for the integration you will have a file called manifest.json
You can add a version key to it yourself. e.g. here’s one of mine:
{
"domain": "bwalarm",
"name": "BWAlarm (ak74 edition)",
"documentation": "https://github.com/akasma74/Hass-Custom-Alarm",
"dependencies": [],
"after_dependencies": ["mqtt"],
"codeowners": ["@akasma74"],
"requirements": ["ruamel.yaml==0.15.100"]
}
And with the version key added:
{
"domain": "bwalarm",
"name": "BWAlarm (ak74 edition)",
"documentation": "https://github.com/akasma74/Hass-Custom-Alarm",
"dependencies": [],
"after_dependencies": ["mqtt"],
"codeowners": ["@akasma74"],
"requirements": ["ruamel.yaml==0.15.100"],
"version": "1.2.3"
}
You can set the version to anything. just follow the format and take particular note that all lines except the last one must have a comma at the end.
After restarting the error should be gone. Then as finity said above contact the maintainer of the custom integration and get them to update the file. In fact have you checked if they have done this already?
There may be a new version to download.