composer error

[linland]

composer require manamine/php-eos-rpc-sdk

Using version ^1.5 for manamine/php-eos-rpc-sdk
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- Installation request for manamine/php-eos-rpc-sdk ^1.5 -> satisfiable by manamine/php-eos-rpc-sdk[v1.5].
- Conclusion: remove vlucas/phpdotenv v3.6.0
- Conclusion: don't install vlucas/phpdotenv v3.6.0
- manamine/php-eos-rpc-sdk v1.5 requires vlucas/phpdotenv ^2.4 -> satisfiable by vlucas/phpdotenv[2.4.x-dev, 2.5.x-dev, 2.6.x-dev, v2.4.0, v2.5.0, v2.5.1, v2.5.2, v2.6.0, v2.6.1].
- Can only install one of: vlucas/phpdotenv[2.4.x-dev, v3.6.0].
- Can only install one of: vlucas/phpdotenv[2.5.x-dev, v3.6.0].
- Can only install one of: vlucas/phpdotenv[2.6.x-dev, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.4.0, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.5.0, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.5.1, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.5.2, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.6.0, v3.6.0].
- Can only install one of: vlucas/phpdotenv[v2.6.1, v3.6.0].
- Installation request for vlucas/phpdotenv (locked at v3.6.0) -> satisfiable by vlucas/phpdotenv[v3.6.0].

Installation failed, reverting ./composer.json to its original content.

Thanks

[ramakrishnaj]

I am also getting this error.
can help anybody ?